Test text
Matches & groups
Enter a pattern and text; matches highlight in the text
Regex
Regex Tester
Live match highlight · Capture groups · Flags · Backtracking guard · Runs locally
Local · No upload
Everything runs in your browser — inputs and results never reach a server.
Ready to use
No signup, no install, works offline.
Free · No ads
Fully free, no popups, no tracking.
Regex Tester Online｜Live Match Highlight｜Capture & Named Groups｜Backtracking Guard｜Runs Locally — No Upload
Live highlight
All matches highlighted in the text as you type.
Capture / named groups
Per-match positions and captured groups, named supported.
All flags
g / i / m / s / u / y (flag list is a placeholder).
Backtracking guard
Runs isolated; aborts on timeout so the page never freezes.
Local · no upload
Pattern and text never leave your browser.