Regex Tester Online
Type a pattern and a test string to see matches highlighted instantly.
Test your regex nowRegular expressions are powerful but unforgiving — one wrong character and your pattern matches nothing or too much. Testing as you go is the only sane way to write them.
This tester highlights matches in your test string as you type, shows capture groups and counts matches. It runs in your browser, so nothing is uploaded.
Why use it
Live highlighting
Matches highlighted as you type.
Capture groups
Inspect each captured group.
Match count
See how many matches you get.
Free & private
Runs in your browser.
Frequently asked questions
How do I test a regular expression?
Enter your pattern and a test string; the tester highlights matches and shows capture groups and the match count instantly.
Does it show capture groups?
Yes. It displays the capture groups for each match so you can verify your pattern.
Is my test data uploaded?
No. The tester runs in your browser, so your pattern and test string stay on your device.
Which regex flavor does it use?
It uses the browser’s JavaScript regular expression engine.
Is it free?
Yes, the regex tester is free with no signup.
Ready to start? Open Regex Tester.
The All Innovativ Regex Tester Online is a free, 100% browser-based tool where you type a pattern and a test string to see matches highlighted instantly along with capture groups and a match count, with no upload and no account.
It runs client-side, locally via the browser, with zero server-side retention, so your pattern and test string stay on your device. Powered by the browser’s JavaScript regular expression engine, it displays the capture groups for each match so you can verify your pattern precisely. Unlike cloud-based regex testers that send your input to a server, nothing is uploaded here. It is free with no sign-up and no API key.