Regex Tester
Test regular expressions against sample text with live match highlighting.
Pattern
Test String
Matches
9 matches
The quick brown fox jumps over the lazy dog.
- The@ 0
- quick@ 4
- brown@ 10
- fox@ 16
- jumps@ 20
- over@ 26
- the@ 31
- lazy@ 35
- dog@ 40
What the tool does
Regex Tester runs regular expressions against sample text with live match highlighting so you can debug patterns faster.
How to use it
- Enter a regular expression.
- Paste sample text to test against.
- Review highlighted matches and adjust flags/pattern as needed.
Supported formats
- JavaScript-style regular expressions and plain text samples
Privacy & security
This tool runs entirely in your browser. Your data never leaves your device — nothing is uploaded to our servers.
FAQs
- Which regex flavor is this?
- It follows JavaScript regular expression behavior in your browser.
- Can I test flags like global or case-insensitive?
- Yes, when flags are exposed in the UI (for example g, i, m).
- Is my text sent to a server?
- No. Testing is local.