InstantQR
🔎 Regex matching • ⚡ Fast UI • 🔒 Runs locally in your browser

Regex Tester

Test regular expressions instantly with pattern flags, match highlighting, and capture group inspection. Great for validation, parsing, debugging, and developer workflows.

Mode
Ready
Shows the latest regex test state.
Flags
g
Current regex flags.
Matches
0
Total number of regex matches.
Groups
0
Total capture groups found.
Test Pattern and Input
Enter a regex pattern, choose flags, and test against your input text instantly.
Ready
Run a regex test to see highlighted matches.
Live result
Updates when you test the regex
Enter a regex pattern and some test text.
Format: /pattern/flags

Matches

Matches will appear here after testing.

Replacement Preview

Add replacement text to preview replaced output.

Inspect match groups

This tool shows each match with its index and capture groups so you can debug patterns more easily.

Local testing

Regex matching runs locally in your browser, making it fast and private for everyday development work.

Related Developer Tools

FAQ

Can I test regex flags like g, i, and m?

Yes. This tool supports common JavaScript regex flags including g, i, m, s, u, and y.

Can I inspect capture groups?

Yes. The tool shows matches and capture groups for each result.

Does this regex tester run locally?

Yes. Regex testing runs locally in your browser.