How to use Regex Validator
- Type or paste your pattern and test string into Regex Validator's input area.
- Use the Pattern, Flags settings to control the result.
- The result is computed live in your browser as you edit the input.
- When it looks right, Copy pattern to save it.
About this tool
Regex Validator runs entirely in your browser. Regex Validator 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. It behaves the same on desktop and mobile, with nothing stored remotely.
Frequently asked questions
What is Regex Validator for?
Regex Validator lets you validate your input right in the browser using the Pattern, Flags controls, with the result shown instantly and nothing uploaded.
Does Regex Validator cost anything?
No — Regex Validator is completely free, with no sign-up and no hidden limits.
Does Regex Validator upload my data?
No — Regex Validator processes everything locally in your browser, so nothing you enter is uploaded or stored.
Which regex flavor does Regex Validator use?
Regex Validator runs your pattern with the browser's own JavaScript regex engine, live and on your device.
Can I use Regex Validator without a connection?
Yes — after the first load Regex Validator runs entirely offline.