Regex Playground

Test regular expressions interactively

Regular expressions are powerful and famously hard to get right, and testing them against real input is the only reliable way. This interactive playground tests regex with syntax highlighting, explanations and match visualisation, so you can build and understand a pattern as you go.

Why interactive testing is essential

A regex that looks correct often is not, matching too much, too little, or not what you meant, and the only way to know is to run it against real examples. A playground that highlights the syntax, explains what each part does, and shows the matches visually turns regex from guesswork into something you can reason about. Seeing exactly what a pattern matches, and why, is how you both fix a broken pattern and learn how regex works. This is far faster and safer than testing a pattern by deploying it and hoping.

Build patterns with confidence

It runs entirely in your browser, so nothing you paste is uploaded and the result is yours to copy straight into a project. Because it works client-side, you can use it on private code and data without anything leaving your machine.

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