Regex Tester
Test regular expressions against any text with real-time match highlighting. It runs entirely in your browser — no signup, no installation, and nothing you paste or drop leaves your device.
What is Regex Tester?
Regex Tester is a free online developer tool built for developers debugging payloads, configs and code. Test regular expressions against any text with real-time match highlighting In practice you enter your regular expression and a test string, set the flags you need, and then read the highlighted matches and adjust the pattern.
Your code, tokens and payloads never leave the browser, which matters when you are debugging something under NDA or handling production data.
How to use Regex Tester
- Enter your regular expression and a test string.
- Set the flags you need.
- Read the highlighted matches and adjust the pattern.
Regex Tester FAQ
Is Regex Tester free to use?
Yes. Regex Tester is completely free and needs no account, no trial and no payment details. Every feature on the page is available without limits.
Is my data uploaded anywhere?
No. Regex Tester runs entirely in your browser, so the text, file or number you enter never leaves your device.
Does Regex Tester work on a phone or tablet?
Yes. It works in any modern browser on desktop, tablet and phone. There is no app to install and no account to create.
How do I use Regex Tester?
Enter your regular expression and a test string. Set the flags you need. Read the highlighted matches and adjust the pattern.