Inspect and compare
Regex Tester
Write a regular expression and see matches, capture groups and replacements highlighted live.
- Runs in your browser
- Instant results
- Free, no sign-up
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How to use the Regex Tester
- Enter your pattern and flags such as g, i or m.
- Paste test text; matches are highlighted as you type.
- Check the capture groups and try a replacement.
Frequently asked questions
Which regex flavor is used?
JavaScript (ECMAScript), as in your browser. Most syntax also works in Python, Java and PCRE.
How do I use capture groups in replacements?
Use $1, $2 and so on for numbered groups, or $<name> for named groups.
Why does my pattern match only once?
Add the g (global) flag to find every match instead of only the first.