How to use Regular Expression Check Online
- Start by adding the text you want to check into Regular Expression Check Online.
- Set Pattern, Flags so the output fits your use case.
- Watch the output update instantly while you adjust the text.
- Finish by choosing Copy pattern to take the output with you.
About this tool
Regular Expression Check Online runs entirely in your browser. Regular Expression Check Online tests your regular expression against sample text in your browser, highlighting matches as you type.
Flags and group captures are surfaced so you can refine the pattern quickly. No data is sent anywhere, so it stays fast and private by default.
Frequently asked questions
What is Regular Expression Check Online for?
Regular Expression Check Online lets you check your input right in the browser using the Pattern, Flags controls, with the result shown instantly and nothing uploaded.
Do I need an account for Regular Expression Check Online?
No — Regular Expression Check Online needs no account, sign-up or installation.
Where is my data processed by Regular Expression Check Online?
Entirely in your browser — Regular Expression Check Online keeps your data on your own machine and sends nothing anywhere.
Which regex flavor does Regular Expression Check Online use?
Regular Expression Check Online runs your pattern with the browser's own JavaScript regex engine, live and on your device.
Can I use Regular Expression Check Online without a connection?
Yes — after the first load Regular Expression Check Online runs entirely offline.