, Replace = `$3-$2-$1` re-orders a date column from `MM/DD/YYYY` to `YYYY-DD-MM`."}},{"@type":"Question","name":"Can I undo the replace?","acceptedAnswer":{"@type":"Answer","text":"There's no undo — but the source CSV is untouched (only the download is rewritten), so just re-run with new settings."}}]}

CSV Find & Replace

Run a find-and-replace across an entire CSV — all columns or just one — with optional case-sensitive and regex modes.

Quick answer: Run a find-and-replace across an entire CSV — all columns or just one — with optional case-sensitive and regex modes.

Last updated 2026-05-01

Frequently asked questions

How do I run find-and-replace on a single CSV column?: Pick the column from the 'Scope' dropdown. Only that column is rewritten; the rest of the row passes through untouched.
Does it support regular expressions?: Yes. Toggle 'Use regular expression' to switch from literal text matching to JavaScript-flavour regex. Useful for things like `\bcustomer-(\d+)` → `cust_$1`.
Are matches case-sensitive?: By default no — `Ada` and `ada` both match. Toggle 'Case-sensitive' on for an exact-case match.
How many replacements does the tool report?: The footer shows the total number of replacements applied across all rows and columns in the chosen scope. Useful for sanity-checking before downloading.
Will my CSV be uploaded?: No. Find & Replace runs entirely in your browser using Papaparse — your data never reaches our server.
Will quoted fields with commas survive the replace?: Yes. The parser is RFC-4180 compliant, so quoting is preserved through the round-trip.
Can I replace newlines or tabs inside cells?: Yes, but only via regex — type `\n` or `\t` in the Find box with regex mode on. Literal mode treats your input as plain text.
What if my regex is invalid?: An error appears below the controls explaining what's wrong, and the preview falls back to the original rows so you don't accidentally download a broken file.
How do I use a backreference in the replacement?: Standard JavaScript syntax: `$1`, `$2`, etc. Example: Find = `^(\d+)/(\d+)/(\d+) CSV Find & Replace — Free Online Tool | Toolbox4Free , Replace = `$3-$2-$1` re-orders a date column from `MM/DD/YYYY` to `YYYY-DD-MM`."}},{"@type":"Question","name":"Can I undo the replace?","acceptedAnswer":{"@type":"Answer","text":"There's no undo — but the source CSV is untouched (only the download is rewritten), so just re-run with new settings."}}]} , Replace = `$3-$2-$1` re-orders a date column from `MM/DD/YYYY` to `YYYY-DD-MM`.
Can I undo the replace?: There's no undo — but the source CSV is untouched (only the download is rewritten), so just re-run with new settings.