Formatting & Validation

Regex Tester

Test regular expressions against real text, inspect matches and capture groups, and toggle common flags without leaving your workflow.

Run a regex against sample text, inspect matches, and explain what the pattern is doing.

Flags
Use JavaScript regex syntax. Add the g flag to list every match instead of only the first one.
2 matches
Match 1index 0

alice@example.com

Match 2index 22

bob@example.com

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flags g2 matches

What is this tool?

Regex Tester helps developers test regular expressions, inspect matches, and debug capture groups quickly. It is especially useful for debugging validation rules, extracting data from logs, reviewing capture groups before shipping code.

How to use it

Paste or enter your regex tester input.
Adjust the mode, options, or sample values for the exact workflow you need.
Review the output, copy the result, and move back into your app or request.

Example

Pattern + text
/\b\w+@\w+\.\w+\b/g on "alice@example.com and bob@example.com"
Matches
alice@example.com, bob@example.com

The tester lists every match and the captured groups so you can see exactly what the pattern is doing.

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Frequently Asked Questions

Regex Tester helps developers test regular expressions, inspect matches, and debug capture groups quickly. It is built for common workflows like debugging validation rules and extracting data from logs.

Use it when you need a fast answer while debugging, building payloads, or validating output. Typical workflows include debugging validation rules, extracting data from logs, reviewing capture groups before shipping code.

Yes. The tool is designed for fast, lightweight workflows without sign-up or heavy UI. Most processing happens instantly in the browser.