Developer tools

Regex lab

A quick sandbox for writing and testing regular expressions.

Set pattern and flags, enter text, then Run to list matches.

Matches

    Guide

    Try regex before production

    What is it?

    A quick sandbox for writing and testing regular expressions.

    Why it matters

    A wrong regex breaks data or matches nothing.

    How it works

    Set pattern and flags, enter text, then Run to list matches.

    Go deeper

    Why you’ll love this

    Try your regex on real sample text before shipping it to production.

    How to jump in

    1. Pattern and flags

      Set the pattern and g/i/m/s.

    2. Enter test text

      Paste a realistic sample.

    3. Run

      Matches list with indexes.

    What you walk away with

    • Common flags
    • Match list
    • No signup
    • Free

    Where it shines

    Input validation

    Test email/code patterns.

    Text extraction

    Preview tokens before scripting.

    Learning

    Practice flags live.

    Quick answers

    Which regex engine?

    Your browser’s JavaScript RegExp engine.

    Does it replace?

    This version focuses on matching and testing.

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