# 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. ## Run it - **CLI:** `gizza tool data-bin "name,score Alice,12 Bob,55 Carol,88 Dan,73" 'column=score'` - **Web:** https://gizza.ai/tools/data-bin/ - **Agents:** machine-readable descriptor (parameters JSON Schema) at https://gizza.ai/tools/data-bin/tool.json ## Inputs - `input` — CSV _(field)_ - `method` — Binning method _(field)_ - `column` — Column to bin (header name or 1-based index) _(field)_ - `bins` — Number of buckets (equal-width / quantile) _(field)_ - `edges` — Custom edges (ascending, comma-separated) _(field)_ - `labels` — Custom bucket labels (one per bucket, comma-separated) _(field)_ - `label_style` — Auto-label style (when labels blank) _(field)_ - `right` — Right-closed intervals ( (a, b] ; off = left-closed [a, b) ) _(field)_ - `precision` — Decimal places in range labels _(field)_ - `output` — Output mode _(field)_ - `header` — First row is a header (kept, used for column names) _(field)_ - `delimiter` — Delimiter _(field)_ ## Output - Binned CSV (text) ## Query parameters Open the tool pre-filled and auto-run via URL: - `input` — CSV - `method` — Binning method - `column` — Column to bin (header name or 1-based index) - `bins` — Number of buckets (equal-width / quantile) - `edges` — Custom edges (ascending, comma-separated) - `labels` — Custom bucket labels (one per bucket, comma-separated) - `label_style` — Auto-label style (when labels blank) - `right` — Right-closed intervals ( (a, b] ; off = left-closed [a, b) ) - `precision` — Decimal places in range labels - `output` — Output mode - `header` — First row is a header (kept, used for column names) - `delimiter` — Delimiter Example: `https://gizza.ai/tools/data-bin/?input=name%2Cscore%0AAlice%2C12%0ABob%2C55%0ACarol%2C88%0ADan%2C73&method=equal_width&column=score&bins=4&edges=0%2C18%2C65%2C120&labels=low%2Cmid%2Chigh&label_style=range&right=true&precision=3&output=append&header=true&delimiter=comma` --- ## Bin a numeric column of a CSV into buckets Paste a CSV, pick one numeric column, and this tool sorts each row into a **bucket** and labels it — locally in your browser, **nothing is uploaded**. Choose how the buckets are drawn: - **Equal-width** — split the column's value range into buckets of the same width. `bins` sets how many (default `4` = quartiles). Simple to read, but a few extreme values can leave some buckets nearly empty. - **Quantile** — draw the edges so each bucket holds roughly the **same number of rows** (equal-frequency). Preferred for skewed data. Duplicate edges from repeated values are merged automatically, so you may get fewer buckets than requested. - **Custom edges** — supply your own strictly-ascending boundaries (like `0,18,65,120`). Values below the first or above the last edge get a blank label. Label each bucket yourself (**Custom bucket labels**, one per bucket) or let the tool auto-label them as an **interval range** (like `(50, 75]`) or a 1-based **bucket index**. **Right-closed intervals** decides whether a boundary value falls in the lower or upper bucket, and **Output mode** either appends a new `_bin` column or replaces the source column with the label. ### Worked example With the default **Equal-width** method and `4` buckets on the `score` column, this input: ``` name,score Ann,0 Bo,40 Cy,70 Di,100 ``` becomes: ``` name,score,score_bin Ann,0,"[0, 25]" Bo,40,"(25, 50]" Cy,70,"(50, 75]" Di,100,"(75, 100]" ``` `score` runs `0`–`100`, so four equal-width buckets have edges `0, 25, 50, 75, 100`. `40` lands in `(25, 50]` and `70` in `(50, 75]`. The first bucket is written `[0, 25]` because the lowest edge is always included; interval labels that contain a comma are quoted by the CSV writer. ### Limits & edge cases - The chosen column must be **numeric** — every present value has to parse as a finite number, or the run errors. `NaN` and `inf` count as non-numeric. - **Blank cells stay blank**: an empty target cell gets no label and is left out of the edge statistics. - With **Custom edges**, a value outside the first/last edge gets a **blank** label rather than being forced into an end bucket. - **Quantile** binning can merge duplicate edges on skewed or repeated data, so the result may have fewer buckets than `bins`. - A **constant** column (all values equal) yields a single bucket. - **Custom bucket labels** must supply exactly one label per bucket, or the run errors — handy because quantile merging can change the bucket count. - Turn off **First row is a header** for files with no header row; then the column selector must use a 1-based index and row 1 is binned like any other. - Everything runs in memory, so very large files are bounded by your browser's available memory. ### FAQ
What is the difference between equal-width and quantile binning? **Equal-width** cuts the value range into buckets that each span the same distance — with `bins = 4` over `0`–`100` you get `0–25`, `25–50`, `50–75`, `75–100` regardless of how many rows land in each. **Quantile** (equal-frequency) instead moves the edges so every bucket holds roughly the same *number of rows*; it's the better choice for skewed data because no bucket ends up nearly empty.
How do I set my own bucket boundaries? Choose **Custom edges** as the method and type strictly-ascending, comma-separated numbers under **Custom edges** — for example `0,18,65,120` makes the buckets `[0, 18]`, `(18, 65]`, `(65, 120]`. Any value below the first edge or above the last one gets a blank label. Pair it with **Custom bucket labels** (like `child,adult,senior`) to name each band.
What do the labels like "(50, 75]" mean? They are interval notation for the bucket's boundaries. A square bracket `[` or `]` means the endpoint is **included**; a round bracket `(` or `)` means it is **excluded**. So `(50, 75]` covers values greater than `50` up to and including `75`. Toggle **Right-closed intervals** off to flip this to `[50, 75)`, or switch **Auto-label style** to *Bucket index* for a plain `1`, `2`, `3`.
Which value goes into which bucket at a boundary? A value exactly on an edge follows the **Right-closed intervals** setting. When it is on (the default), intervals are `(a, b]`, so a boundary value falls in the **upper** bucket — except the very lowest edge, which is always included. Turn it off for `[a, b)` intervals, where a boundary value falls in the **lower** bucket and the very highest edge is included.
Is my data uploaded anywhere? No. The whole computation runs locally with WebAssembly; your CSV never leaves your browser.
## Related tools - [Adjacency Matrix Converter](https://gizza.ai/tools/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](https://gizza.ai/tools/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. - [Avro to JSON Converter](https://gizza.ai/tools/avro-to-json/): 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](https://gizza.ai/tools/bank-statement-reconcile/): Match bank-statement CSV rows to ledger rows by date, signed amount, and fuzzy memo similarity, with unmatched and suggested matches. - [Base64 ⇄ Base64url Converter](https://gizza.ai/tools/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.