Regex tester
Test JavaScript regular expressions against text in your browser. Patterns and samples stay local.
No uploads. No account. Free to use.
4 match(es)
The quick brown fox
- Files never leave your device
- Runs entirely in your browser
- No signup required
- Free
What is regex tester?
The regex tester runs JavaScript RegExp against sample text and lists matches.
How to use it
- Enter a pattern, flags, and sample text.
- See matches using native RegExp.
- Nothing is sent to a server.
When to use it
Patterns and production logs stay in the page. Cap input size so a catastrophic pattern cannot freeze the tab forever.
Frequently asked questions
Are my files uploaded?
No. This tool runs in your browser. Files and text stay on your device and are not sent to our servers.
Does this use AI?
No. It is a deterministic utility. There is no model and no third-party processing of your data.
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