Bulk Find and Replace (multiple rules at once)
Apply several find-and-replace rules in order, as plain text or regular expressions, with match case and whole-word options. Preview every change and undo after applying the result.
- Runs in your browser (no upload)
Up to 200,000 characters
Replacement rules (applied from top to bottom)
In regular expressions, $1 or $<name> inserts what was matched, and ^ and $ match the start and end of each line. "Whole words only" matches only when no letter or digit is directly before or after. Empty rules are ignored.
Replacing…
Replacements run in a separate thread in your browser and stop automatically after 2 s (protection against runaway regular expressions).
How to use
- Paste the text you want to change.
- Enter "Find" and "Replace with", and choose regular expression, match case or whole words if needed. Add as many rules as you like; they run from top to bottom.
- Check the preview (red = removed, green = added), then copy or save the result, or apply it to the text. Applying can be undone.
FAQ
In which order are the rules applied?
From top to bottom. Each rule runs on the text produced by the rules above it. Use the ↑ and ↓ buttons to reorder them.
What can I use in regular expressions?
JavaScript regular expressions in Unicode mode. In the replacement, $1, $<name> and $& insert what was matched. ^ and $ match the start and end of each line.
Can a complex regular expression freeze the page?
No. Replacements run in a separate thread (a Web Worker) and are stopped automatically after 2 seconds, with an error message.
Notes & limitations
- What you enter is processed only on this page and is not sent to YUCTS servers.
- Texts up to 200,000 characters, up to 30 rules, and results up to 2,000,000 characters.
- Undo covers only "apply result to the text", up to the last 20 times. History and rules are lost when you close the page.
- "Whole words only" checks that no letter, digit or underscore is directly before or after a match, so it does not work as expected for languages written without spaces, such as Chinese or Japanese.
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