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CSV (Comma-Separated Values) utilities, in the browser
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Convert, view, and clean CSV (Comma-Separated Values) in seconds.

browser-based CSV utilities · updated 9 May 2026

A growing collection of browser-based CSV tools for the awkward parts of the job — converting, viewing, cleaning, and reshaping. Everything runs in your browser, nothing uploaded.

Convert (all reversible)
View & check
Clean
Reshape

Converting between formats

If you have a CSV and need JSON, the CSV → JSON converter handles both plain arrays and JSON Lines (NDJSON), with RFC 4180-correct quoting and a "keep everything as strings" default so you don't silently lose leading zeros or boolean-looking fields. Going the other way, the JSON → CSV converter accepts both shapes and produces valid CSV that Excel and every library I tested will read cleanly. For loading a CSV into a database, the CSV → SQL generator emits batched multi-row INSERT statements for PostgreSQL, MySQL, SQLite and SQL Server, with an optional CREATE TABLE built from type inference over the whole file.

Looking at a CSV

Sometimes you just want to see the data. The CSV viewer renders a file as a sortable, filterable in-browser table — click any header to sort, type in the filter box to narrow rows, and export only the rows you see. It's the tool I open first when a support ticket lands on my desk with a CSV attached.

Reshaping a CSV

A handful of tools for when the file isn't in the shape you want. The merge tool stacks multiple CSVs by row, or outer-joins them on a shared key column. The dedupe tool strips duplicate rows by any subset of columns, with optional case-insensitive and whitespace-tolerant comparison. The diff tool compares two versions of a CSV and highlights added, removed, or changed rows at the cell level — much better than plain diff for tabular data. And when a file is too big for the consumer, Split CSV chops it by row count or by column value into a ZIP of smaller files, each a standalone CSV with its header preserved.

What they have in common

Everything runs in your browser. The files you drop or paste never leave your machine — there is no server component handling data. I can't see your rows because they were never sent to me. That means no size cap beyond your browser's memory (typically 500 MB to 1 GB per file on a laptop), no account required, and nothing for me to leak. See the privacy policy for the longer version.

Sensible defaults, no hidden magic. Values stay as strings unless you explicitly ask otherwise (so 007 stays "007" and doesn't turn into the number seven). Quoting follows RFC 4180. Delimiters are auto-detected, but the status bar tells you what was picked. Nothing gets silently transformed.

Free to use, with no warranty. Read the terms of use before relying on the output for anything load-bearing. Bug reports, corrections, and feature requests are always welcome — drop me a line.

— S., [email protected]