Regex Tester
Test JavaScript regular expressions with live match highlighting, capture groups, substitution, and shareable links.
About this tool
Test JavaScript regular expressions with live matches, capture groups, flags, and replace previews. Free online regex debugger; data stays in your browser. Regex Tester runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.
What this tool does not do
- Regex Tester is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.
How do I use this tool?
How do I use Regex Tester?
Open Regex Tester, enter or paste your input, and copy the result. The page works without an account.
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