Regex Tester
Test and debug regular expressions with live highlighting. See matches and groups as you type. Runs entirely in your browser.
Start by pasting or typing — your data stays in your browser.
Tip: Ctrl+Enter to run, Esc to clear
Quick examples
Matches: 0
How to use
- 1
Enter a pattern
Type a regular expression in the pattern field and select flags (g, i, m, s, u, y) as needed.
- 2
Add test text
Paste or type sample text. Matches are highlighted live as you edit the pattern or text.
- 3
Inspect matches
Review the match count, each match index, capture groups, and named groups in the results list.
Frequently Asked Questions
No. All regex testing happens locally in your browser.
Invalid syntax shows a clear error message without breaking the page. Fix the pattern and testing resumes automatically.
With the g flag, all non-overlapping matches are found. Empty matches advance the search index to avoid infinite loops.
Yes. Use the example buttons for email, phone, and URL patterns to fill the pattern and test text instantly.
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