Regex Tester — Free Online
Test patterns and see every match and group. Works in your browser, no install needed.
Free with a CeevTech Tools account — no credit card required.
How to use Regex Tester
Type your Pattern and set the Flags (g is set by default).
Paste text into the Test string box.
Read the match count, positions and groups as you type.
Why use CeevTech Regex Tester?
Writing a regular expression is trial and error until it matches exactly what you want. CeevTech Regex Tester runs your JavaScript regex against sample text as you type and lists every match with its position and capture groups. Syntax errors are reported straight away. Use it to test regex online for form validation, log parsing or search-and-replace work.
- Fast: processes your code or data in seconds.
- Private: runs in your browser, so nothing is uploaded.
- Works everywhere: desktop, tablet and phone, in any modern browser.
- One account, 79+ tools: PDF, image, office, AI, developer and business tools in one place.
Frequently asked questions
Which regex flavour does it use?
It uses the JavaScript RegExp engine in your browser, so flags such as g, i, m, s and u work. Syntax specific to PCRE or Python may behave differently.
Why do I only see one match?
Without the g flag only the first match is returned. Add g to the Flags box to list all matches, up to 500.
Is Regex Tester free?
Free with a CeevTech Tools account — no credit card required.
Do I need to install anything?
No. Regex Tester runs online in your browser on Windows, Mac, Linux, Android and iPhone.
Is my data private?
Yes. Regex Tester runs entirely in your browser, so your data never leaves your device.