CSV Editor: how it works
How it works
- Open a UTF-8 CSV, TSV or TXT file with the button above, or drop it into the workbench. Check the detected delimiter, encoding, line endings and row count before you change anything.
- Click a cell and type a replacement, then press Enter to finish the edit. Undo and redo step through completed edits one at a time. Doctor lists nine checks, and you can preview a repair such as trimming spaces or removing duplicate or blank rows before applying it.
- Choose Save & verify. If the file picker gave this page a file handle and you allow writing, it writes back to the file you opened and reads it again to verify the result. Without a handle, as with a dropped file, it starts a download instead. Denying write access cancels the save.
What stays exactly the same
Records outside edits and repairs keep their original bytes, except that removing the last row can adjust the new last row's line ending. Editing a cell rewrites its entire row, including cells you did not change, so quoting can differ. Trimming spaces rewrites affected rows; removing rows drops them. Check the save report before writing.
Undo restores the exported bytes from before the edit, and redo brings the edit back. Opening a new file starts a fresh history. Your file is uploaded to the cellsmith.app server, held in memory and deleted after the retention period; a planned desktop app is meant to edit files on your own computer. It is not released yet.
Limits
Files are uploaded to the cellsmith.app server and held in memory, not kept only in your browser. The web version accepts UTF-8 text files up to 32 MiB each. Files expire 30 minutes after the last activity; opening another file or restarting the server also clears the current document and unsaved work.
Questions about this tool
How do I edit a CSV file online?
Open the file, click a cell, type the new value and press Enter. The table shows every field as text. When you are done, choose Save & verify to write the file or download it.
Can I undo an edit?
Yes. Each completed cell edit is one undo step, and redo brings it back. Undo restores the previous exported bytes. Opening another file clears the history.
Does editing convert 001 to 1?
No. Cell values stay text. Another application, such as Excel, may still convert them when you open the saved file there.
Will saving overwrite my original file?
Only if you opened it with the file picker, your browser gave this page a file handle and you allow writing. Then Save & verify writes to that file and reads it back. A dropped file has no handle, so saving starts a download. If you deny write access, the save is cancelled.
Does saving change the parts of the file I did not edit?
Editing a cell rewrites its whole row, so even unchanged cells in that row may have different quoting. Records outside edits and repairs keep their original bytes, except that removing the last row can adjust the new last row's line ending. Trimming spaces rewrites affected rows, and removing rows drops them. Check the save report before writing.
Is my file uploaded?
In the web version, yes: the file is sent to the cellsmith.app server to build the table, kept in memory and deleted after the retention period. The planned desktop app is meant to edit files on your own computer; it is not released yet.