Reshape JSON, YAML, CSV & XML with a query
Paste any JSON, YAML, CSV, or XML document and reshape it with a JSONata expression — filter, aggregate, and build a new structure, output as JSON or YAML. Runs entirely in your browser, no upload.
Reshape any structured data with one query
Paste a document in JSON, YAML, CSV, or XML, write a JSONata expression, and get a brand-new structure back as JSON or YAML. It replaces the usual "convert to JSON → run a query → template the output" dance with a single step, across all four input formats. Everything runs locally in your browser with a pure-Rust engine — your data is never uploaded to a server.
JSONata is one small language for both querying (navigate paths, filter with predicates, aggregate) and templating (construct new objects and arrays). Set the input format, or leave it on Auto-detect to sniff it from the content.
Worked example — CSV in, summary object out
Input (CSV):
name,price
apple,2
banana,3
cherry,5
Query:
{ "total": $sum($.price), "items": $count($), "cheapest": $min($.price) }
Output (JSON):
{
"total": 10,
"items": 3,
"cheapest": 2
}
CSV rows arrive as an array of objects (here $ is that array), and numeric
cells are coerced to numbers so $sum/$min work directly.
More examples
orders.{ "id": id, "total": $sum(lines.amount) }— reshape each object into a new shape.items[price > 10].name— filter with a predicate, then project a field.$sum(order.item.price)— aggregate values pulled from nested XML elements.{ "name": user.first & " " & user.last }— combine YAML fields into a new object.$sort($, function($a, $b){ $a.price > $b.price })— sort an array with a comparator.
Notes and limits
- Input formats: JSON, YAML, CSV (with a header row), and XML. CSV becomes an
array of row objects; XML elements map to nested objects (attributes are keyed
with a leading
@, repeated tags become arrays). - Output formats: JSON or YAML. Pretty-print applies to JSON only; YAML is always block style.
- Type coercion: CSV and XML text that looks numeric or boolean is coerced to
real numbers/booleans so arithmetic and aggregation work; empty CSV cells become
null. - A query that matches nothing returns
null— this is normal in JSONata, not an error. - Object key order in the output follows the engine's serializer.
FAQ
What query language does this use?
It uses JSONata, a lightweight expression language for querying and
transforming structured data. A single expression can navigate paths
(account.orders.total), filter (items[qty > 0]), aggregate ($sum, $count,
$max, $average), and construct new objects and arrays
({ "id": id, "total": $sum(lines.amount) }). Because the input is parsed into a
common model first, the same expression works whether you started from JSON,
YAML, CSV, or XML.
How is CSV turned into something I can query?
CSV is parsed with its first row as headers into an array of objects — one
object per data row, keyed by the header names. Reference the whole array as $
(for example $sum($.price)) or a single field as price. Cells that look like
numbers or true/false are converted to real numbers and booleans, and empty
cells become null, so aggregation and comparisons behave as expected.
How does XML map onto the query model?
Each XML element becomes an object keyed by its child element names; repeated
child tags collapse into an array; attributes are included under keys prefixed
with @; and text/number/boolean-looking content is coerced to JSON scalars. So
<order><item><price>10</price></item></order> lets you write
$sum(order.item.price).
Why did my query return null?
In JSONata a path that matches nothing yields undefined, which this tool
normalizes to null. The usual causes are a key-name or case mismatch, or
querying an object where an array was expected (or vice versa). Genuine problems
— a syntax error in the expression or an unparseable input document — are
reported as errors, not null.
Is my data uploaded anywhere?
No. Parsing, the JSONata evaluation, and serialization all run inside your browser via WebAssembly. Nothing is sent to a server, so you can reshape private or sensitive data safely.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool data-reshape "name,price
apple,2
banana,3
cherry,5" 'query={ "total": $sum($.price), "items": $count($) }'New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/data-reshape/?data=name%2Cprice%0Aapple%2C2%0Abanana%2C3%0Acherry%2C5&query=%7B%20%22total%22%3A%20%24sum%28%24.price%29%2C%20%22items%22%3A%20%24count%28%24%29%20%7D&input_format=auto&output_format=json&pretty=trueMachine-readable descriptor: tool.json — title + parameters JSON Schema for agents.