Free Regex Tester Online (Regular Expressions)
Use this free regex tester to test regular expressions against text and see matches. Fast, private, and works in your browser.
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What is Regex Tester?
Regex Tester runs a JavaScript regular expression against your test text and highlights every match, with capture groups and match counts. It is useful for building and debugging patterns. Everything runs in your browser.
How to use this tool
- Enter your regular expression and flags.
- Paste the test text.
- See matches highlighted with groups.
Features
- Test against any text
- Flags (g, i, m, s, u)
- Highlights all matches
- Shows capture groups and match count
- Runs entirely in your browser
This tool runs in your browser. Your files and text are not uploaded to our servers, and we do not store your input.
Frequently asked questions
Which regex flavor is used?+
JavaScript (ECMAScript) regular expressions, the same as in browsers and Node.
What if my pattern is invalid?+
You will see a clear error message so you can fix the pattern.
Is my text uploaded?+
No. Matching happens entirely in your browser.
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