Regex Tester
Test regular expressions with live match highlighting. Supports flags and capture groups. Runs in your browser.
100% private
Pattern + text
Matches
Auto-playing walkthrough — paste input, click test, see the result
Flags
Highlighted Matches
Enter pattern and textHow to use Regex Tester
- Enter your regular expression pattern.
- Select flags (global, case-insensitive, multiline, etc.).
- Type test strings and see matches highlighted in real time.
Frequently Asked Questions
- Is there a regex timeout?
- Yes. Patterns that could cause catastrophic backtracking are aborted after a short timeout to protect your browser.