Regex Tester

Test JavaScript regular expressions with live match highlighting.

Regular expression

Flags: g global · i ignore case · m multiline · s dot matches newline · u unicode

Test string

Contact alice@example.com or bob@test.com for details.
Support: help@fabcodelabs.com

Matches

Replace with use $1, $2 for groups

How to use the Regex Tester

Write and debug regular expressions with live highlighting, capture group details and a replace preview.

Instant resultsEverything updates live as you type. No buttons to wait on.

PrivateYour input never leaves your browser and is never stored.

Free foreverNo signup, no limits and no paywall.

Works offlineInstall the site as an app and use it anywhere.

Is the Regex Tester free?

Yes, it is 100% free with no signup, no watermarks and no usage limits.

Is my data private?

Yes. Everything is calculated in your browser. Nothing you type is sent to or stored on a server.

Does it work on phones and tablets?

Yes. The tool works in any modern browser on Android, iPhone, iPad, Windows, Mac and Linux.