Data tools
CSV, JSON, YAML, XML and friends — convert, query, diff, format and clean structured data.
Absolute value, sign, or negation for a whole column
Paste a column of numbers and apply absolute value, sign extraction (-1/0/1), sign flipping, or force-negative to every value at once, with rounding and an audit table.
Adjacency Matrix Converter
Convert a graph between edge list, adjacency matrix, and incidence matrix — directed or undirected, weighted or not. Free, private, runs in your browser.
Amazon Order Analyzer
Paste an Amazon order-history CSV export to summarize total spend by month, top items, and category breakdowns. Browser-only, private, with Markdown or JSON output.
ARFF Converter
Convert Weka ARFF datasets to CSV and CSV tables back to ARFF locally — nominal attributes, numeric types, dates, sparse rows, missing values, and type rows.
Fit Audio to an Exact Length
Make any audio file an exact number of seconds — pad it with silence when it's short or trim it when it's long. Runs in your browser, nothing uploaded.
Audio RMS level report
Measure per-channel RMS, sample peak, average level, headroom, DC offset, and clipped samples from pasted audio bytes as JSON, CSV, or a text report.
Avro to JSON Converter
Decode Apache Avro Object Container Files (.avro / OCF) to JSON, NDJSON, or the embedded schema — no .avsc needed, free and private in your browser.
Reconcile bank statement and ledger CSVs
Match bank-statement CSV rows to ledger rows by date, signed amount, and fuzzy memo similarity, with unmatched and suggested matches.
Base64 Validator
Validate Base64 and Base64url strings in your browser — find invalid characters, padding mistakes, mixed alphabets, line-length issues, and decoded size.
Base64 ⇄ Base64url Converter
Convert standard Base64 to URL-safe Base64url and back in your browser — swaps +/ for -_, handles = padding, auto-detects direction. Free, private, no sign-up.
Beancount to CSV Converter
Flatten Beancount or Ledger journal postings into spreadsheet-ready CSV, then rebuild a simple journal from that flat CSV schema.
Bencode decoder
Decode bencode (the BitTorrent / .torrent serialization format) into readable JSON, and re-encode JSON back into canonical bencode — in your browser. Nothing is uploaded.
BibTeX Formatter & Validator
Free BibTeX formatter and validator — pretty-print, sort and align .bib bibliography entries in your browser. Consistent indentation, no sign-up, no upload.
BSON Inspector
Paste BSON bytes as base64 or hex and inspect a typed tree or canonical MongoDB Extended JSON v2 with ObjectId, dates, binary, and int64 preserved.
Budget Planner
Plan a monthly budget from take-home pay: 50/30/20 needs/wants/savings targets with custom splits, or a zero-based plan showing what's left to allocate.
CAMT.053 Statement Parser
Parse a camt.053 (or camt.052/054) ISO 20022 bank statement XML into JSON or CSV in your browser: balances, dates, counterparties, references. No upload.
Cartesian to polar CSV converter
Convert a whole CSV of (x, y) points to polar (r, θ) coordinates in your browser, in degrees or radians, keeping your other columns intact.
Category Canonicalize
Paste a CSV, TSV, or newline list plus a variant-to-canonical mapping, then rewrite categorical values and review fuzzy suggestions for anything not covered.
Validate a PEM certificate chain offline
Check a pasted PEM certificate chain offline for leaf-to-root ordering, signature linkage and expiry windows.
Check digit validator
Validate or compute check digits for Luhn cards, IMEI, NPI, ISBN-10/13, ISSN, EAN/UPC/GTIN/SSCC, IBAN, ABA routing, ISIN and VIN codes.
Churn cohort retention
Build monthly, weekly, or daily cohort retention and churn tables from signup and activity CSV data, with weighted averages and export formats.
Rebalance an imbalanced CSV label column
Rebalance an imbalanced CSV label column by seeded random over- or under-sampling of whole rows toward a target class ratio. Reproducible, in-browser, no synthetic rows.
Cluster Similar Values
Group near-duplicate values in a column (typos, casing, spacing) and get a canonical form per cluster. Runs in your browser, nothing is uploaded, free.
Color converter
Convert a color between HEX, RGB(A), HSL, HSV and CMYK, in your browser. Paste any notation and get them all. Nothing is uploaded.
Compare one column across two tables, matched by key
Join two CSVs on a key column and report every row where a single chosen value column disagrees, as clean old → new pairs. Browser-local, no upload.
Drop constant columns from a CSV
Find and remove constant (zero-variance) columns from a CSV — columns with one repeated value or all blanks. In-browser, no upload.
Cookie String to JSON
Parse a raw HTTP Cookie header string into JSON — name/value object or an array of {name, value} pairs, with optional URL-decoding. Free, in your browser.
Prune highly correlated features
Drop multicollinear numeric columns by thresholded Pearson, Spearman, or Kendall correlation. In-browser, no upload.
CSS Color Converter
Paste any color — hex, rgb, hsl, hwb, oklch, oklab, a CSS name or 0xAARRGGBB — and get every other notation for it, plus CMYK, Display P3 and WCAG contrast.
Find CSV rows with no matching key
Return rows in CSV A whose key has no match in CSV B, or the reverse, with composite keys, alternate delimiters, and browser-local processing.
CSV Cell Diff
Compare two CSVs column-by-column and highlight every individual cell that changed, plus added and removed rows and columns.
Change CSV Delimiter
Re-save CSV or delimited data with a different separator (comma, tab, semicolon, pipe) with correct requoting — in your browser. Free, private, no upload.
Generate a Chart from CSV
Paste CSV data and generate a bar, line, scatter, or histogram chart as a clean, scalable SVG — in your browser, nothing uploaded. Pick columns, colors, and size.
CSV Cleaner
Clean a messy CSV in your browser: trim whitespace, remove duplicate rows, drop empty rows, fill blanks, and normalize delimiters. No upload, free.
CSV Coalesce Columns
Merge CSV columns into one by taking the first non-empty value per row, in the priority order you choose. Add a fallback, drop the sources. Free, in-browser.
Collapse CSV rows into one cell per group
Group CSV rows by key columns and join another column into one delimited cell, with dedupe, sorting, and browser-local processing.
CSV Column Mapping Suggest
Suggest source-to-target CSV column mappings using fuzzy header similarity and sampled value overlap. Outputs confidence scores, reasons, and unmapped columns.
CSV Column Splitter & Concatenator
Split a CSV column into multiple columns by delimiter, or concatenate columns into one. Header-aware, trim options, exact CSV output, in-browser.
CSV Column Type Validator
Validate CSV columns against declared types like int, float, bool, date, and enum, with row/line reports for every offending cell.
CSV Date Normalizer
Normalize a CSV date column to ISO 8601, Unix time, SQL, or a custom pattern. Infers day-first vs month-first per column. Free, runs in your browser.
CSV Dedupe
Remove duplicate rows from a CSV, keeping the first — optionally keyed on chosen columns. Runs in your browser, nothing is uploaded, free.
CSV Fill Down
Forward-fill empty CSV cells with the last non-empty value above them, like a spreadsheet fill-down. Fill up too, pick columns. Runs in your browser, free.
CSV Filter
Keep only the CSV rows that match a condition (e.g. age > 30, city == NYC, name contains al) — numeric or string, in your browser. Free, private, no upload.
Find incomplete CSV rows
Scan a CSV for malformed rows: too few or too many fields, or blank cells in required columns. Runs in your browser. Free, private, no upload.
CSV Formula Eval
Add or transform CSV columns with spreadsheet-style formulas (e.g. total = price * qty) — runs in your browser. Free, private, no upload.
CSV Group By
Group CSV rows by a column and aggregate others (count, sum, average, min, max) — in your browser. Free, private, no upload.
CSV Header Sanitizer
Clean messy CSV column names into valid snake_case, camelCase, or kebab-case identifiers. Fixes blanks and leading digits, deduplicates collisions. Free, in-browser.
CSV Insert Column
Add a new column to a CSV at any position, filled with a constant value — in your browser. Free, private, no upload.
CSV Join
Join two CSV files on a key column, SQL-style — inner, left, right, or full outer. Different key names, custom delimiter, case control. In your browser, no upload.
CSV ⇄ JSON Converter
Convert CSV to JSON or JSON to CSV in your browser — auto-detects direction, infers types, handles quoted fields and custom delimiters. Free, no upload.
CSV Null Standardizer
Paste a CSV or TSV and rewrite NA, N/A, #N/A, NULL, NaN, None, dashes and blank cells into one missing-value token. Runs locally in your browser.
CSV PII redactor
Mask, salted-hash, or redact the values in chosen CSV columns for safe sharing — pick columns by name or index, in your browser. Free, private, no upload.
CSV Pivot Table
Build a pivot table from a CSV — group by rows, spread a column's values across columns, aggregate (sum/count/avg/min/max). Runs in your browser, free, no upload.
CSV Query
Query a CSV with SQL-style SELECT, WHERE, ORDER BY, and LIMIT — right in your browser. Free, private, no upload.
CSV Quote Normalizer
Paste a CSV to fix mixed quoting — backslash escapes, single or curly quotes, stray quotes — and re-emit it as clean RFC 4180. Runs in your browser.
CSV Regex Find and Replace
Run a regex find-and-replace on chosen CSV columns, with $1 capture groups. Quoted fields stay intact. Free, runs entirely in your browser.
CSV reorder columns
Reorder, swap, or drop CSV columns by name or index to a target order, in your browser. Free, private, no upload.
Add a Row Index, UUID, or Key Column to CSV
Add sequential row numbers, UUIDs, or composite key columns to CSV data online. Choose the delimiter, header handling, position, padding, prefix, and suffix.
CSV Sample
Take a random, systematic, top-N, bottom-N, or stratified sample of rows from a large CSV. Reproducible by seed, in your browser — no upload, no sign-up.
CSV Sort
Sort CSV or TSV rows by one or more columns, ascending or descending, numeric-aware or lexical. Multi-key with per-column direction. Runs in your browser, free.
CSV stats
Compute per-column count, distinct, min, max, mean and sum for a CSV, in your browser. Free, private, no upload.
Validate CSV structure
Validate CSV structure online: find ragged rows, inconsistent column counts, unclosed quotes, and stray delimiters with line numbers. Free, private, in-browser.
CSV timeline viewer
Paste a CSV, TSV or JSON Lines event log and filter it by time range, search every column, sort, pick columns and page through the matches locally.
CSV to GeoJSON Converter
Convert CSV, TSV, pipe, semicolon, or JSON coordinate tables into GeoJSON points, lines, or polygons with typing, bbox, and invalid-row controls.
CSV to ICS
Paste a CSV of events and get an .ics calendar file to import into Google Calendar, Outlook or Apple Calendar. Free, private, runs in your browser.
CSV to Ledger
Convert a bank or credit-card CSV export into double-entry ledger/hledger journal transactions. Auto-detects columns, guesses accounts, runs in your browser.
CSV to NDJSON Converter
Convert CSV to NDJSON in your browser — one JSON object per row for streaming pipelines, with type inference and custom delimiters. No upload.
CSV to PDF Table
Render CSV, TSV, semicolon, or pipe-delimited data as a formatted PDF table with headers, pagination, page size, orientation, font size, grid, and banding controls.
CSV to SQL
Convert CSV or JSON rows into SQL CREATE TABLE and INSERT statements with inferred column types for MySQL, PostgreSQL, SQLite, SQL Server, or ANSI SQL. Free, in-browser.
CSV to table
Convert CSV data into a Markdown or HTML table, in your browser. Free, private, no upload.
CSV to vCard Converter
Convert CSV or JSON contact lists into a single .vcf vCard file for iPhone, Android, Google Contacts, Outlook, and CRM imports.
CSV to Excel (.xlsx)
Convert CSV, TSV or JSON into a real Excel .xlsx workbook — typed number/boolean columns, a bold frozen header, auto-fit widths. In-browser, nothing uploaded.
CSV to XML
Convert a CSV table into XML records using the header names as element tags, in your browser. Free, private, no upload.
CSV to YAML
Convert a CSV table into a YAML list of objects keyed by the header row, in your browser. Free, private, no upload.
CSV transpose
Transpose a CSV — swap rows and columns so the header becomes the first column — in your browser. Free, private, no upload.
CSV Type Inferrer
Paste CSV and get a JSON schema: auto-detected delimiter, header row, and per-column types (int, float, bool, date, datetime, string). Runs in your browser.
CSV Whitespace Normalizer
Paste a CSV or TSV to trim every cell, collapse or remove the spaces inside values, and clean up non-breaking spaces. Runs locally in your browser.
CSV Window Functions
Add SQL window-function columns to CSV rows in your browser: running total, moving average, lag, lead, rank, dense_rank, and row_number, with partition and order support.
Currency Converter
Convert an amount between currencies using an exchange-rate table you paste. Chains multi-leg rates, reverses rates automatically, no live data. Free & in-browser.
Data Binning Tool
Bin a numeric CSV column into equal-width, quantile (equal-frequency), or custom-edge buckets and label each row. Runs entirely in your browser, free — nothing uploaded.
Cluster Tabular Data
Paste CSV data and cluster it with KMeans, DBSCAN, or hierarchical methods, then export an SVG scatter plot, labeled CSV, or JSON report.
Data drift summary
Paste a baseline and a current CSV to get a per-column drift report: type, null rate, cardinality, range, new or missing categories and a PSI or JSD score.
Data Format Converter
Convert data between CSV, TSV, JSON, and NDJSON (JSONL) in any direction — auto-detects the source, infers types, unions keys. Free, in-browser, no upload.
Identify a data sample's format, delimiter and columns
Paste a data sample and find out what it is: CSV, TSV, JSON, JSON Lines, XML, HTML, fixed-width or binary, plus delimiter, quote char, encoding and column types.
Reshape JSON, YAML, CSV & XML with a query
Parse JSON, YAML, CSV, or XML and reshape it with JSONata into new JSON or YAML — filter, aggregate, and restructure in one browser-local step.
Data Validator
Validate pasted CSV or JSON rows against field rules — required, unique, type, range, length, regex, enum — and list every violation. Free, runs in your browser.
Date Column Validator
Check every value in one CSV date column against a chosen format — ISO, US, EU, RFC 3339, or a custom pattern — with a per-row report of invalid dates.
Date Format Normalizer
Paste text with dates in mixed formats and get them all rewritten to ISO 8601 or any format you pick, with the day/month order settled from the text. Free and private.
Dotenv Validator
Paste a .env file to catch duplicate keys, unquoted spaces, malformed ${VAR} interpolation and undefined references. Runs locally in your browser.
Downsample Time-Series (LTTB)
Reduce a large time-series to a target point count with LTTB, min/max, M4, or every-nth downsampling — shape preserved, in your browser, no upload.
Analyze max drawdown and recovery time
Analyze an equity curve or return series for maximum drawdown, drawdown duration, recovery time, current drawdown, ulcer index, pain index, and top drawdown episodes.
DynamoDB JSON Converter
Convert between DynamoDB typed AttributeValue JSON and plain JSON in both directions, with auto-detect and pretty or compact output.
Elasticsearch Bulk Formatter
Build a compact Elasticsearch _bulk API body from a JSON array. Choose index/create/update/delete, _index, _id field, and doc_as_upsert locally.
Email syntax validator
Validate email address syntax offline, flag disposable domains and role-based mailboxes, and get a pass/fail verdict with a low/medium/high risk grade.
Email Validator
Validate an email address against RFC 5321/5322 syntax in your browser — flags bad domains, illegal characters and typos like gmial.com. Free, no DNS lookup.
Env Schema Validator
Paste a .env file and a schema to catch missing, mistyped and out-of-range variables before your app boots. Rules or JSON Schema. Runs in your browser.
FASTQ to FASTA Converter
Convert FASTQ sequencing reads to clean FASTA in your browser — strip quality lines, filter by length and mean quality, wrap, rename, discard N reads. No upload.
FIT File Decoder
Decode a Garmin/ANT .fit activity file (pasted as base64) into a readable summary, a per-record CSV, or a GPX track — locally in your browser, no upload.
Fixed Width to CSV Converter
Convert fixed-width records to CSV. Auto-detect aligned whitespace or enter exact widths/ranges, headers, delimiters, quoting, and line endings.
Flatten JSON
Flatten nested JSON into single-level dot or bracket key paths, or unflatten those paths back into nested JSON. Custom separator, CSV/pairs output, no upload.
Form Field Validator
Validate a whole form locally: email, phone, URL, postal code, and credit card fields with required checks, locale hints, normalization, and JSON.
CSS Formatter
Pretty-print CSS, SCSS, or LESS locally. Choose indentation, sort declarations, split selectors, and normalize hex colors in your browser.
Format Validator
Validate a value as an email address, URL, IPv4/IPv6 address, phone number, or credit card with Luhn check. Auto-detect formats locally in your browser.
Analyze a conversion funnel
Paste an event CSV and compute funnel conversion and drop-off rates per step. Unique users, conversion from top and previous step — in your browser, no upload.
Fuzzy CSV Join
Join two CSV tables on approximately matching key values, with similarity scores, join modes, unmatched-row reports and multiple matching algorithms.
Fuzzy Name Matcher
Match and deduplicate person or organization names with Jaro-Winkler, Levenshtein and Soundex. Paste names, tune the threshold, export groups, pairs, CSV or JSON.
Find missing numbers and gaps in a sequence
Paste invoice numbers, order IDs, cheque numbers, or any sequence that should be consecutive to find missing values, gap ranges, and duplicates.
Google Drive Link Converter
Turn a Google Drive share link into a direct-download, embed, preview, or thumbnail URL — or extract the file ID. Handles large-file scan warnings.
Convert VCF Variants to TSV
Flatten Variant Call Format (VCF) records into tidy TSV, exploding INFO fields and optional sample genotype columns. Runs locally in your browser.
Geo Cluster
Cluster latitude and longitude points by real ground distance with DBSCAN or a grid. Get cluster assignments and centroids, entirely in your browser.
Point in Polygon Checker
Test latitude/longitude points against a polygon geofence. Paste GeoJSON or lat,lon lines, choose boundary handling, and export text, CSV, or JSON.
GeoJSON formatter and minifier
Format GeoJSON locally: pretty-print, minify, round coordinates, reorder keys, add bbox, fix winding, and prune properties.
GeoJSON Merge
Merge multiple GeoJSON files, features, or geometries into a single FeatureCollection. Round coordinates, renumber ids, tag by source — in your browser, nothing uploaded.
GeoJSON to CSV Converter
Flatten GeoJSON features into CSV rows with property columns, WKT or longitude/latitude geometry, nested-field flattening, and delimiter options.
GeoJSON to SVG
Render GeoJSON to a scalable SVG map in your browser — polygons, lines and points, Web-Mercator or raw lon/lat, custom colours. No tile server, no upload.
GeoJSON validator
Validate GeoJSON in your browser. Report every structural error, polygon winding violation, and out-of-range coordinate with a JSON path.
Gmail Takeout mbox → CSV / JSON
Turn a Google Takeout Gmail .mbox export into CSV or JSON — one row per message with date, from/to/cc, subject and Gmail labels. In-browser, no upload.
GPX Analyzer
Paste a GPX file to get total distance (km and miles), elevation gain/loss, duration, average speed and pace — in your browser. Nothing is uploaded.
GPX Merge
Merge several GPX files, tracks, routes and waypoints into one GPX 1.1 file, ordered chronologically by timestamp. Runs in your browser; nothing is uploaded.
GPX Privacy Scrubber
Scrub a GPX file before sharing it: remove or fuzz start/end locations, rewrite timestamps, and strip sensor extensions. Runs locally in your browser.
GPX Simplifier
Paste a GPX track and reduce its point count with Douglas-Peucker tolerance in meters while preserving route shape, endpoints, elevation and times.
GPX Splitter
Split a GPX track into multiple segments by distance, elapsed time, or detected stop gaps. Output a new GPX or a per-segment summary locally in your browser.
GPX to CSV Converter
Convert a GPX track, route or waypoints to clean CSV in your browser — latitude, longitude, elevation, time, derived speed and sensor data. Free, private, no upload.
GPX / KML to GeoJSON Converter
Convert GPX or KML GPS tracks and waypoints into GeoJSON, or GeoJSON back into GPX, entirely in your browser. Free, private, no upload.
GPX to KML Converter
Convert GPX tracks, routes, and waypoints into KML for Google Earth. Set line color, width, opacity, waypoint color, and altitude mode locally.
HAR Validator
Validate a HAR file against the HAR 1.2 spec: log/entries shape, request/response/timing fields, exact JSON paths, and timing totals.
HCL to JSON
Convert HashiCorp HCL2 / Terraform configuration to JSON. Handles blocks, labels, repeated blocks, expressions, sorting, compact or pretty output.
Histogram Bin Calculator
Work out how many bins a histogram needs. Compare Sturges, Scott, Freedman-Diaconis, Rice and square-root, then get the bin edges, counts and percentages.
HL7 v2 Message Parser
Parse an HL7 v2.x message into named segments, fields, components and subcomponents in your browser. MSH, PID, OBX and more, as JSON or CSV. No upload, free.
HTML Validator
Validate an HTML document or snippet and get every syntax error, unclosed tag, and nesting issue with line and column — runs locally in your browser.
Extract & Validate IBANs
Paste an invoice, email or statement and pull out every IBAN, each checked with the ISO 13616 mod-97 checksum — in your browser. Nothing is uploaded.
IBAN Validator
Validate an IBAN with the mod-97 checksum and parse out the country, bank, and account — instantly, in your browser. Nothing is uploaded, free.
ICS to CSV Converter
Convert an .ics calendar file to CSV in your browser — one row per event with summary, start, end, location and description. Free, private, nothing uploaded.
INI / .env Diff
Compare two .env or .ini config files key-by-key: added, removed and changed settings, with case-folding and secret masking.
INI ⇄ JSON Converter
Convert INI/conf files to JSON and JSON back to INI, or get, set and delete a single key while keeping comments, blank lines and key order intact.
INI Parser
Convert INI/conf files to structured JSON, handle sections, comments and quoted values, and report duplicate keys locally in your browser.
Run jq on JSON
Run a jq program against any JSON document right in your browser — filter, map, select, reshape. Pure-Rust jq (jaq), nothing is uploaded, free.
JSON Array Pluck Field
Paste a JSON array, wrapper object, or NDJSON and extract one key or dotted path from every row as lines, CSV, TSV, JSON, or a custom-delimited list.
JSON Beautifier
Pretty-print minified or messy JSON with configurable indentation (or minify it), validating it in the process. Runs in your browser; nothing is uploaded.
Convert stringified JSON values back to real types
Paste JSON where every value is quoted and get real types back: numbers, booleans and nulls. Protects ZIP codes, big integers and chosen keys.
JSON Array Deduplicator
Remove duplicate elements from a JSON array: compare whole values or chosen key fields, keep the first or last occurrence, or list the duplicates instead.
JSON Diff
Compare two JSON documents and see exactly what was added, removed or changed, with full JSON paths — in your browser. Nothing is uploaded.
JSON Error Locator
Paste broken JSON and get the exact line, column and cause of every syntax error, with a caret-marked snippet and a suggested fix. Runs in your browser.
JSON Escape / Unescape
Escape or unescape special characters in a string for safe use inside JSON — quotes, backslashes, newlines, control chars. Runs in your browser; nothing uploaded.
Extract JSON from Logs
Paste mixed log or console text and extract embedded JSON objects and arrays — validated, pretty-printed, and separated into blocks in your browser.
JSON Key Case Converter
Rename every JSON key to camelCase, PascalCase, snake_case, kebab-case or SCREAMING_SNAKE_CASE. Values stay untouched. Runs in your browser.
JSON-LD Schema Markup Generator
Generate schema.org JSON-LD structured data for Article, Product, FAQ, Organization, Event, Recipe and more — a ready-to-paste script tag, free in your browser.
Format and filter structured JSON logs
Pretty-print JSON log lines, flatten nested fields, filter by level or field, and export readable logs as text, table, JSON, or CSV.
JSON Mask
Prune a JSON document to just the fields you name with a mask like a,b(c,d) — the Google Partial-Response syntax. Free, in your browser.
JSON Merge
Deep-merge two or more JSON objects, with configurable array handling and last-wins conflict resolution — in your browser. Nothing is uploaded.
JSON entity normalizer
Normalize deeply nested JSON into id-keyed entity tables plus a result id, using a compact entity schema and deterministic local WASM.
JSON Path Editor
Get, set, or delete a value at a dotted or bracketed path in a JSON document. Supports array indices, quoted keys, and auto-created intermediates.
JSON Redact
Detect and mask secrets — API keys, tokens, passwords, private keys and emails — in a JSON document before sharing. Structure-aware, in your browser, nothing uploaded.
JSON Null Remover
Recursively remove null values from JSON, and optionally empty strings, arrays and objects. Compact or keep array positions, pretty-print or minify.
JSON Repair
Fix broken JSON automatically — trailing commas, single quotes, unquoted keys, missing commas, comments, truncated LLM output. Runs in your browser.
JSON Schema Batch Validator
Validate a JSON array or NDJSON batch against one JSON Schema. Get a pass/fail summary plus per-record errors with JSON Pointer paths — locally in your browser.
JSON Schema compatibility check
Compare old and new JSON Schemas for consumer/backward and producer/forward compatibility. Flags enum, type, required-field, object, array, and bound changes.
Generate fake data from a JSON Schema
Generate deterministic fake JSON, JSONL, or CSV rows from a JSON Schema subset with formats, enums, ranges, arrays, and seeds.
Generate a sample JSON instance from a JSON Schema
Paste a JSON Schema and get a minimal valid example JSON instance. Honors required, default, const, enum, examples, $ref, allOf and formats. Runs in your browser.
JSON Key Sorter
Recursively sort JSON object keys A→Z or Z→A for clean diffs. Supports case-insensitive sorting, optional array sorting, and indent or minify.
JSON structure analyzer
Analyze a JSON document's structure: max nesting depth, node counts, key frequency, per-path types, and array stats — in your browser. Free, private, no upload.
Convert JSON to a DynamoDB BatchWriteItem payload
Convert a JSON array of objects into a DynamoDB BatchWriteItem request payload with typed AttributeValues. Put or delete, pretty or compact, up to 25 items.
JSON to Graph
Turn JSON into a node-link graph as Mermaid flowchart or Graphviz DOT. Collapse deep branches, cap arrays and generate paste-ready diagram source in your browser.
JSON to HTML Table
Render a JSON array or object as a clean HTML table or Markdown table with nested-value controls.
JSON to JSON Schema
Paste JSON and get a JSON Schema — types, required fields, unions, and formats (email, uri, date-time, uuid) inferred. Draft 2020-12 or Draft-07, in-browser, free.
JSON to Markdown Converter
Convert JSON exports, API responses or config files into nested Markdown. Objects become bullets and headings; arrays become tables or lists.
JSON → SQL INSERT Generator
Turn JSON objects or arrays into SQL INSERT statements — MySQL, Postgres, SQLite, SQL Server, or ANSI, with literals or placeholders.
JSON to TypeScript
Paste JSON and get TypeScript interfaces — nested types, optional fields, and unions inferred automatically. Runs in your browser, nothing is uploaded, free.
JSON to XML Converter
Convert JSON to well-formed XML with configurable root and array item names, attributes, text nodes, pretty printing, and an optional XML declaration.
JSON Transform Rules
Reshape JSON with declarative target = selector rules, JSONPath-style selectors, defaults, transforms, merge mode, and a rule report.
JSON ⇄ YAML ⇄ TOML
Convert config data between JSON, YAML, and TOML in any direction — in your browser. Round-trips through a common model. Nothing is uploaded.
JSON ⇄ YAML Converter
Convert between JSON and YAML in either direction, right in your browser. Auto-detects the input format. Nothing is uploaded, free.
JSON5 / JSONC ⇄ JSON Converter
Convert JSON5 or JSONC to strict JSON — strip // comments and trailing commas, quote keys — or turn plain JSON back into JSON5. Private, in-browser, free.
Query & transform JSON with JSONata
Run a JSONata expression against any JSON document right in your browser — query, filter, aggregate, and reshape JSON. Pure-Rust engine, nothing is uploaded, free.
JSONL stats
Summarize JSON Lines records: record count, per-key coverage, value-type distribution, distinct counts, samples, and numeric/string stats.
JSONPath Query
Evaluate JSONPath expressions (RFC 9535) against any JSON in your browser — wildcards, slices, recursive descent, filters. Free, private, nothing uploaded.
Key-value text parser
Parse messy key: value or key=value text into JSON, grouping repeated keys, splitting blank-line records, and preserving ordered pairs with line numbers.
KML / KMZ to GeoJSON Converter
Convert KML or KMZ map data into GeoJSON — or GeoJSON back into KML — entirely in your browser. Free, private, no upload, no account.
Kruti Dev to Unicode Converter
Convert legacy Hindi Kruti Dev 010 font text to standard Unicode Devanagari (Mangal font) and vice versa. Safe, offline, client-side conversion.
Convert LDAP LDIF exports to CSV
Paste an LDAP LDIF export and flatten entries into CSV rows, with DN, repeated attributes, base64 values, changetype records and delimiter controls.
Least Squares Regression Calculator
Fit linear, quadratic, or polynomial least-squares models to pasted x,y data. Get coefficients, R², residuals, predictions, CSV, and JSON — all locally.
Ledger Balance
Paste a ledger-cli or hledger plain-text journal and get the balance of every account and sub-account, as a tree, CSV, JSON or Markdown. Runs in your browser.
Ledger Register
Paste a ledger-cli or hledger plain-text journal and list matching postings with running totals, filters, CSV, JSON and Markdown output. Runs in your browser.
Likert Scale Summary
Summarize Likert survey answers: item means, SD, median, mode, distributions, top/bottom-box percentages, and text stacked bars. Runs in your browser.
List Converter
Convert, clean and sort lists online — comma-separated to lines, SQL IN, JSON, XML or custom delimiters, with prefix, dedupe and case options. Free, in-browser.
Location History Parser
Turn Google Takeout or Dawarich location-history JSON into per-day places visited and distance traveled. Text, CSV, or JSON; km or miles.
Logfmt Converter
Convert log data between logfmt, JSON, NDJSON and CSV in any direction — auto-detects the source, infers types, writes real logfmt. Free, in-browser.
Luhn Validator
Validate a credit card, IMEI, or any number against the Luhn check-digit algorithm — instantly, in your browser. Nothing is uploaded, free.
MAC Address Format Converter
Reformat MAC addresses between colon, hyphen, Cisco dotted-quad, and bare hex — in lower or upper case. Paste one or many; runs in your browser, nothing uploaded.
Markdown Table Formatter
Format GitHub-flavored Markdown tables online — even column widths, tidy delimiter rows, alignment kept or forced. Free, in your browser, no upload.
Markdown Table to CSV
Convert Markdown or pipe-delimited tables into clean CSV. Strip alignment rows and padding; choose delimiter, quoting, line endings, header, and BOM.
Read a Mattermost Bulk Export
Paste a Mattermost bulk export (import.jsonl) and get a readable per-channel transcript with resolved authors, timestamps, threads and a summary. Runs locally.
Extract MFCC Features from Audio
Extract MFCC features from audio as CSV, TSV, or JSON. Tune speech defaults, librosa-style settings, deltas, and sample-rate options locally.
MIDI to JSON
Convert a Standard MIDI File (.mid/.midi) to JSON — paired notes with pitch names, a raw event stream, or a compact summary. Free, runs in your browser.
Missing Value Imputer
Fill missing cells in a CSV with mean, median, most-frequent, a constant, or KNN imputation. Pick columns and missing markers. Runs in your browser, free.
Missing Value Report for CSV / TSV
Paste a CSV or TSV table and get per-column missing-value counts, percentages, and a missingness-pattern grid. Handles custom NA tokens. Runs locally in your browser.
Monte Carlo Simulation
Run Monte Carlo simulations in your browser: define input distributions, a formula, and trials, then get percentiles, target probability, and a histogram.
MessagePack to JSON
Paste MessagePack hex or base64 and decode it into pretty-printed JSON. Preserves field order, uint64 values, timestamps, and binary payloads in your browser.
MT940 Statement Parser
Parse a SWIFT MT940 bank statement into JSON or CSV in your browser: balances, dates, debit/credit, amounts, references and narrative. No upload, free.
Multiple linear regression calculator
Paste a numeric data matrix and fit an OLS multiple regression: coefficients, p-values, confidence intervals, R², adjusted R² and F-test.
NDJSON / JSON Lines Filter
Filter and reshape NDJSON (JSON Lines) in your browser. Keep rows with a predicate, pick or rename fields, and export as JSONL, a JSON array, or CSV.
NDJSON to matrix
Turn NDJSON / JSON Lines records into one aligned table: unified columns from dotted paths, chosen fill for missing cells, CSV, TSV, matrix or JSON out.
NDJSON Viewer
Paste NDJSON / JSON Lines and read it: pretty, compact, array or table view, search any key or value at any depth, and per-line error reporting.
Net Worth Calculator
Paste your assets and liabilities and calculate net worth with a per-category breakdown, proportional bars, and a debt-to-asset ratio. Runs in your browser.
NEXUS to FASTA Converter
Convert NEXUS DATA or CHARACTERS sequence matrices to FASTA locally, with interleaved matrices, comments, matchchar expansion, TAXA labels, gaps, and wrapping.
NMEA to CSV
Convert raw NMEA 0183 GPS/GNSS sentences into a timestamped CSV track with latitude, longitude, altitude, speed, course and fix quality.
NPY Array Decoder
Decode a NumPy .npy file in your browser: read its dtype, shape and byte layout, and export the array values as JSON or CSV. No Python, no NumPy, no upload.
Format a Number as Currency
Format a pasted number as currency with symbols or codes, grouping, decimal places, rounding, signs, accounting parentheses and locale-style separators.
Numeric Range Check
Flag CSV numeric values outside an expected min/max range, with column selection, delimiter detection, and text or JSON reports.
Numeric Row Deduplicator
Remove duplicate numeric rows from CSV/TSV in your browser. Compare cells by value, key on selected columns, apply rounding tolerance, and keep first or last.
Clean messy number cells into floats
Strip currency symbols, thousands separators, units, percents, and stray whitespace from messy spreadsheet number cells and parse them into clean floats.
OPML ⇄ JSON ⇄ CSV Converter
Convert OPML subscription files (podcast/RSS exports) to and from JSON and CSV in any direction — in your browser. Folders round-trip; nothing is uploaded.
Outline to JSON
Turn an indented text outline into nested JSON in your browser — spaces or tabs, children-array or nested-object shape, pretty or minified. Free, private.
Convert OwnTracks Exports to GPX
Convert OwnTracks JSON or Recorder .rec exports into GPX 1.1 tracks with timestamps, elevation, segments, and optional OwnTracks extensions.
PCA and t-SNE visualizer
Paste a numeric table, reduce it to 2D with PCA or deterministic t-SNE, and get an SVG scatter plot colored by label, plus CSV/JSON coordinates.
Phone Number Formatter & Validator
Parse, validate and format any international phone number — E.164, national and international formats, country and line type. Free, in-browser.
JSON → PHP serialize()
Convert JSON to PHP serialize() format in your browser — byte-accurate strings that PHP's unserialize() can read. Free, private, no sign-up.
PHP unserialize() → JSON
Decode a PHP serialize() string to readable JSON in your browser. Inspect PHP sessions and WordPress wp_options values. Free, private, no sign-up.
PHYLIP to FASTA Converter
Convert PHYLIP alignments to FASTA in your browser. Sequential and interleaved layouts, strict or relaxed taxon names, gap stripping. Nothing is uploaded.
Plist viewer
Parse XML plist or Base64 binary bplist data and render it as readable JSON or a plutil-style tree. Free, private, in-browser.
Podcast feed parser
Parse a pasted podcast RSS/XML feed into clean JSON with episode titles, dates, durations, and audio enclosure URLs. Free, private, in-browser.
Portfolio Allocation Calculator
Paste holdings and calculate percentage allocation by asset class, holding, sector, or account with chart-ready values and concentration score.
Postman / Insomnia Collection Converter
Paste a Postman Collection v2 or Insomnia export and get curl commands, JavaScript fetch() or axios code for every request, with variables filled in. Browser-only.
Principal component analysis (PCA) calculator
Paste a numeric data matrix and run PCA: eigenvalues, explained variance, scree plot, loadings, and projected scores.
Prisma Schema from SQL
Convert SQL CREATE TABLE / ALTER TABLE DDL into a Prisma schema — models, fields, @relation from foreign keys, indexes and native types — locally in your browser.
Prisma Schema to SQL
Convert a Prisma schema into SQL CREATE TABLE DDL — columns, primary keys, indexes, enums and foreign keys — for PostgreSQL, MySQL, SQLite or SQL Server, in your browser.
Protobuf Wire Decoder
Decode raw protobuf wire bytes (base64 or hex) into a field-number/wire-type tree — no .proto schema needed, nested messages recursed. Free, in your browser.
Python Dict to JSON Converter
Convert a Python dict or list literal to valid JSON in your browser — handles True/False/None, single quotes, tuples, trailing commas and comments.
QIF / OFX to CSV Converter
Convert QIF, OFX and QFX bank exports to clean normalized CSV in your browser — Date, Amount, Payee, Memo, Category and more. Free, private, no upload.
Query Result Formatter
Turn raw query result rows — a JSON array, CSV, or TSV — into a clean, aligned Markdown or ASCII table for docs and chat.
Random Bytes Generator
Generate cryptographically secure random bytes and output them as hex, Base64, Base64URL, binary, decimal, a C array or a Python bytes literal.
Random Token Generator
Generate cryptographically secure random tokens, API keys, and secrets with a configurable length and character set — entirely in your browser, nothing uploaded, free.
Regex Capture Groups to CSV
Scan text with a regex and get CSV: one row per match, named capture groups as columns. Pick the delimiter, quoting, and columns — all in your browser.
Validate a CSV column with a regex
Validate one CSV column against a regex, with header or index selection, delimiter auto-detect, blank handling, inverted matching, and text or JSON reports.
Regex to JSON
Parse each line of text with a named-capture regex and turn it into structured JSON — group names become keys. Type coercion, NDJSON output, in your browser.
Regression model trainer
Fit linear, ridge, or bounded random-forest regression from a pasted numeric table and report R², RMSE, MAE, coefficients, or feature importance.
Resume to JSON
Paste a plain-text resume and get a JSON Resume (v1.0.0) document — or validate an existing resume.json against the schema. Runs in your browser.
Returns risk analyzer
Paste a returns series and compute annualized return, volatility, Sharpe, Sortino, Calmar and max drawdown, in your browser. Free, private, no upload.
Convert SAM Alignment Records to CSV
Convert SAM sequence-alignment records into CSV or TSV with named columns, decoded FLAG bits, optional tag columns, filters, and computed spans.
Schema Inferrer
Infer JSON Schema and SQL CREATE TABLE from CSV or JSON samples. Detect column types, nullability, and formats locally in your browser.
JSON array set diff
Compare two JSON arrays as sets: union, intersection, difference and symmetric difference, matched on whole values or on an id field, with counts.
Smart Quotes Converter
Free online smart quotes converter: turn straight ASCII quotes into curly typographic quotes (and back), with correct opening/closing detection. Runs in your browser.
JSON Array Sorter
Sort a JSON array of objects by one or more fields, ascending or descending. Supports nested dot-paths, per-key direction, missing-value placement, and minify.
Sorted Order Checker
Check whether a list of numbers is sorted ascending or descending and see exactly where the order first breaks. Free, runs in your browser.
Spending Categorizer
Paste a bank or credit-card CSV export to auto-categorize every transaction by merchant keywords and summarize spending by category. Runs in your browser.
Smooth a noisy numeric series with a cubic spline
Fit a cubic smoothing spline to noisy numeric data. Choose automatic GCV/CV smoothing, p, lambda, or target degrees of freedom and return JSON, CSV, or SVG.
SQL Dialect Converter
Convert SQL between PostgreSQL, MySQL and SQLite in your browser — rewrites identifier quoting, auto-increment columns and CREATE TABLE data types. Free, no upload.
SQL Dump → CSV
Paste a SQL dump and pull the rows out of its INSERT statements into CSV — one CSV per table, with delimiter, header, NULL and quoting options. Free, private, no upload.
SQL Schema Extractor
Parse CREATE TABLE and ALTER TABLE statements from a SQL dump into a clean table, column, and constraint model as JSON or Markdown — locally in your browser.
Stepwise feature selection for regression
Run forward, backward, or bidirectional stepwise OLS regression on a numeric table to choose predictors by AIC, BIC, AICc, or p-value thresholds.
Structured Data Validator
Validate schema.org structured data from pasted HTML — extract JSON-LD, microdata and RDFa and flag markup errors, locally in your browser.
Subscription Finder
Paste bank or card transactions to find recurring charges, forgotten subscriptions, next charge dates, and projected yearly cost. Free and private.
Subscription Cost Tracker
Add up every recurring subscription, normalize each billing cycle to a monthly and annual figure, and see the biggest spend to cancel. Private, in-browser.
Super timeline builder
Merge parsed forensic artifact CSVs into one sorted UTC timeline with expansion, dedupe, filters, and CSV/l2tcsv/TLN exports.
Survey Tabulator
Tabulate survey CSV responses into frequency tables and two-way cross-tabs with counts, percentages, and a chi-square test. Free, private, runs in your browser.
Table heatmap
Shade a CSV/table's numeric cells with a spreadsheet-style color scale and get a styled HTML table. Free, private, no upload.
Task Format Converter
Convert task lists between todo.txt, Markdown checklists, JSON, and CSV while preserving priorities, tags, and dates.
TCX to GPX Converter
Convert Garmin TCX workout files into GPX 1.1 in your browser. Preserves trackpoints, elevation, timestamps, and heart rate/cadence. Free, private, no upload.
Read a Telegram result.json Export
Paste a Telegram Desktop result.json export and get a clean transcript, per-sender message and word stats, top words and emoji. Runs locally.
Text to JSON
Paste INI, key=value / .env, logfmt, CSV, or /etc/passwd-style text and get clean JSON. Auto-detects the format, infers types, and runs entirely in your browser.
Text to Table
Render delimited text (CSV, TSV, or custom-separated data) as an aligned ASCII or Markdown table.
Time series generator
Generate deterministic synthetic time-series CSV, TSV, JSON or NDJSON with configurable trend, seasonality, noise, missing values and outliers.
TopoJSON to GeoJSON Converter
Convert TopoJSON to GeoJSON in your browser. Decodes shared arcs, delta encoding and the quantization transform into standard RFC 7946 features.
Time Series Decomposition
Paste a time series and split it into trend, seasonal and residual components with STL or classical decomposition. SVG plot plus CSV/JSON components.
Read Your Twitter/X Archive
Paste tweets.js from your Twitter/X data export and get a readable transcript, posting stats, top hashtags and top tweets. Runs entirely in your browser.
TypeScript to JSON Schema
Paste a TypeScript interface, type alias or enum and get JSON Schema — optional props, literal unions, $refs, JSDoc. Draft 2020-12 or Draft-07, in-browser.
Unit Converter
Convert between units of length, mass, temperature, volume, area, speed, data size, and time — instantly in your browser. Names and symbols accepted. Nothing is uploaded.
Unix timestamp converter
Convert Unix timestamps (seconds, milliseconds, microseconds, nanoseconds) to UTC dates, or parse human-readable dates back to epoch timestamps. Free, private, no upload.
Value Counts for a CSV Column
Count distinct values in a chosen CSV column with counts and percentages. Pick a header or column index, sort by count or value, and include blanks if needed.
vCard Duplicate Remover
Find and merge duplicate contacts in a vCard (.vcf) file. Match on name, email, or phone; merge into one card or drop extra copies. Runs in your browser.
Normalize vCard Contacts
Normalize vCard address books locally: lowercase emails, format valid phone numbers, tidy names, and preserve custom fields.
vCard to JSON
Convert vCard (.vcf) contact cards to a clean JSON array. Parses vCard 2.1/3.0/4.0, splits names and addresses, keeps phone/email types. Runs in your browser.
Convert a Voice Note
Convert WhatsApp, Telegram, Signal and other Opus/Ogg voice notes to MP3 or WAV, or encode audio back to Opus voice notes in your browser.
WAV Samples to JSON
Paste an uncompressed WAV as base64 or hex and get JSON: the sample rate, channels, bit depth and duration alongside the PCM samples as an array. Runs in your browser.
WAV to CSV Samples
Paste an uncompressed WAV as base64 or hex and export its decoded PCM samples to CSV: one column per channel, with a time or sample index. Runs in your browser.
Weighted Random Sampler
Draw weighted random samples from CSV or JSON rows, with or without replacement. Seeded, reproducible, and browser-local.
Analyze an Exported WhatsApp Chat
Paste an exported WhatsApp chat to count messages per person, busiest hours and days, and top words and emoji. Fully in-browser — nothing is uploaded.
XML formatter
Pretty-print or minify XML with indentation control and a well-formedness check, in your browser. Nothing is uploaded.
XML to CSV
Flatten repeated XML elements into a CSV table, with columns inferred from child tags and attributes, in your browser. Free, private, no upload.
XML to JSON
Convert an XML document into an equivalent JSON structure, preserving attributes and nesting, in your browser. Free, private, no upload.
XPath query
Run an XPath 1.0 expression against XML or XHTML and return matching node values or serialized XML. Local browser WebAssembly tool.
Deep-merge YAML documents with Helm-style overrides
Deep-merge YAML documents left-to-right with Helm-style overrides. Choose array strategy, precedence, null deletion, key sorting and indentation.
YAML Formatter
Reindent and normalize messy YAML with consistent spacing. Pick indent width, sort keys, or switch between expanded block and compact flow style.
YAML Path Query
Query, set or delete YAML values by dotted and bracketed paths in your browser — dot keys, list indexes, quoted keys, JSON output, and comment-preserving edits.
YAML Resume to HTML
Turn a JSON Resume document written in YAML or JSON into one self-contained, print-ready HTML résumé with themes, accent color, fonts and page setup.
YAML to CSV
Flatten a YAML list or mapping of records into CSV with a unioned column header. Nested keys become dot-paths. Runs in your browser, no upload.
YouTube Takeout stats
Parse Google/YouTube Takeout watch-history JSON or HTML into top channels, repeated videos, monthly trends, weekdays, hours, streaks, CSV, and JSON.