How to view and edit a CSV file
- Drop a CSV or TSV file onto the page, or choose one.
- Click a column name to sort, use the search box to filter, and click a cell then press Enter to edit it.
- Add or delete rows and columns, then export the result as CSV, TSV, or JSON.
Turn off "First row is the header" for files without column names; columns are then labelled A, B, C like a spreadsheet. Numbers sort as numbers and empty cells always sort last.
Questions
Is my file uploaded?
No. The file is read and parsed by your browser in a background thread. It never leaves your device.
How big a file can it open?
The table only draws the rows you can see, so scrolling stays smooth with hundreds of thousands of rows. The limit is your device’s memory: a desktop handles files of a few hundred megabytes, a phone much less. Some browsers cap the height of a scrolling area, so past about 500,000 rows you may not be able to scroll to the very end; filter or sort to reach them.
How do I edit a cell?
Click a cell and press Enter (or double-click it), type, then press Enter to save or Escape to cancel. You can also select a cell and start typing to replace its content. Delete clears it.
Does sorting or filtering change my file?
No, they only change what you see. Exports include the rows currently shown, in the order shown, with any cell edits. To export everything, clear the search first.
Which separators and encodings work?
Commas, tabs, semicolons, and pipes are detected automatically, and you can pick one by hand if the guess is wrong. Files are read as UTF-8 text. Changing the separator reloads the file and drops edits.
Credits
Built on Papa Parse (MIT). OneTooling is not affiliated with that project.