CSV Editor

A table editor for CSV files — right in the browser

The CSV Editor opens, edits, and exports CSV files in a full spreadsheet interface. You load a file, click through the cells like in any spreadsheet app, and save the result back out as CSV, as JSON, or as a Markdown table. What sets it apart: the delimiter and the character encoding are detected automatically, and none of it ever leaves your browser.

CSV sounds simple but rarely is in practice. Sometimes a comma separates fields, sometimes a semicolon (the norm for Excel exports in German and many other European locales), sometimes a tab. Fields containing commas sit inside quotes, quotes get doubled, Excel likes to store accented characters in Windows-1252 rather than UTF-8 — and in the end nobody knows what the file is actually built with. The CSV Editor takes the guesswork off your hands: it detects delimiter and encoding, parses the file cleanly per RFC 4180, reports problems such as a quote that is never closed together with the line number, and lays the result out as an editable table.

The tool is built for everyone who handles CSV files occasionally or regularly: developers who want to inspect a dataset quickly or turn it into JSON; editorial and marketing people who need to fix an export from a shop or newsletter tool; and anyone who just wants to make a foreign, "broken" CSV file readable again. No account, no installation, no upload to someone else's server.

Import: file, drag-and-drop, or clipboard

There are three ways to get data in:

Open brings up the file dialog (accepts .csv, .tsv, and .txt up to 50 MB).
Drag-and-drop: pull a file straight onto the editor area.
Paste reads tabular data from the clipboard — handy for dropping in a selection from Excel, Google Sheets, or Numbers.

All three use the same delimiter detection and the same parser. If First row is header is enabled in Settings, the first row becomes the column headers instead of a data row — and the switch also applies immediately to a table that is already open.

The table editor

The table itself is a full spreadsheet editor (built on Jspreadsheet CE). You can edit cells directly; insert, delete, move, and resize rows and columns; rename columns; and sort by column — numbers numerically, text in natural order, empty cells always last. A right-click opens a context menu with the relevant actions, Undo and Redo (also via Ctrl+Z / Ctrl+Y) step back and forward, and a Transpose function swaps rows and columns. A search box filters the table live, and a fullscreen mode hides everything but the editor. Every cell is plain text — formulas are never executed — and even files with tens of thousands of rows stay responsive.

The status bar below the table shows the current size (rows × columns), the active cell, and — for a multi-cell selection — the sum, average, minimum, and maximum of the numbers it contains. It understands German-style numbers such as 1.234,50 just as well as English ones.

Automatic delimiter detection

By default the import delimiter is set to Auto-detect. The editor test-parses the first 30 lines with comma, semicolon, tab, and pipe (|) and picks the character that splits the lines into columns most consistently. Delimiters inside quotes don't count, and a lone title line above the actual table won't throw detection off. If you know the format or detection gets it wrong, set the delimiter to one of the four fixed values in Settings; the open file is then read again right away.

The editor detects the character encoding on its own, too: a byte order mark takes precedence; otherwise the file is read as UTF-8, and only if it contains invalid bytes does the editor fall back to Windows-1252 — with a notice, so you know what happened. If needed, you pick the encoding by hand.

Export: CSV, JSON, Markdown, or clipboard

Four ways back out — the downloaded files are named after the file you opened:

CSV downloads the table as a CSV file — by default with the delimiter of the opened file, cleanly RFC 4180-compliant with correctly placed quotes. For Excel you can have a UTF-8 BOM prepended and defuse values that start with =, +, -, or @ against formula injection.
JSON downloads the table as a JSON file. With header mode on you get an array of objects (column header as key); otherwise an array of row arrays.
Markdown downloads the table as a Markdown table — with right-aligned number columns, ready for a README, a wiki, or your docs.
Copy copies the entire table tab-separated to the clipboard — ideal for pasting straight into Excel or Google Sheets.

The table's context menu also offers Save as… (or Ctrl+S). That is the spreadsheet library's raw export: tab-separated, as Sheet1.csv, without the export settings and without formula protection — for clean files, use the buttons.

Everything stays in the browser

The CSV Editor is a purely client-side application: no server upload, no account, no transfer of your data. The file is read locally in the browser, edited, and downloaded again. That matters especially for CSV files, which often hold sensitive data — customer lists, orders, exports from internal systems. That data stays on your machine.

So your work survives a reload, the tool automatically saves the table to your browser's LocalStorage after every change and shows in the status bar when it last did so. That, too, is purely local — the storage lives in your browser, not in a cloud. If a table is too large for browser storage, the status bar warns you; then exporting is the only way to keep your changes. Reset clears the table and the saved data again.

Try it now

→ Open the CSV Editor — load a file via Open or drop it in, edit, export as CSV, JSON, or Markdown. No account, free, right in the browser.

CSV is rarely the final format — these tools pick up from here:

JSON Editor — format, validate, and further reshape the data produced by the JSON export.
Convertor PRO — convert between JSON, YAML, TOML, XML, and more when CSV/JSON isn't the target.
Markdown Editor — drop the exported Markdown table into a document and check it in the live preview.
Source Viewer — review an exported file with syntax highlighting.

There's more on the subpages: the manual with every function and option in detail, hands-on examples, and a collection of tips & tricks.