A find-and-replace across a whole document, with optional whole-word matching and full regular expression support. Useful anywhere a text editor's built-in version is too limited, or where the text itself is too sensitive to paste into an online editor you don't control.
When you'd use this
Bulk-renaming a repeated value across a large config or data file, cleaning up formatting inconsistencies across a document, or running a regex pattern to catch variations a plain text match would miss.
Common errors
A regex pattern that matches nothing usually has an unescaped special character in it. Parentheses, periods, and brackets all mean something specific in regex syntax, and matching them literally means escaping them (\., \(, \)).
Whole-word matching won't catch a term buried in a hyphenated or punctuated compound, such as "cat" inside "cat-food". The boundary rule is working as intended there. "Word boundary" carries a specific technical meaning that doesn't always line up with intuition.
Frequently asked questions
Is my text ever sent anywhere to run the replace?
No. The whole operation, regex matching included, runs in your browser. That's the reason this exists separately from an online regex tester: plenty of text is fine to send to a server, but not every document should be pasted somewhere you don't control.
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