Regex Tester

Test regular expressions with real-time matching and explanation

Formatters & Validators Runs in your browser

Regular Expression

Presets:

Test String

How to Use

1Enter your regular expression pattern or choose a preset

2Toggle flags to customize matching behavior

3Paste your test string in the text area

4Matches are highlighted in real-time with alternating colors

5View match details including groups and capture indices

Frequently Asked Questions

What is a regular expression?

A regular expression (regex) is a pattern used to match character combinations in strings. It's widely used for searching, validating, and replacing text.

What do the flags mean?

g = global (find all matches), i = case insensitive, m = multiline (^ and $ match line boundaries), s = dotAll (. matches newlines too).

Is my data safe?

Yes, all regex testing happens in your browser using JavaScript's native RegExp engine. No data is sent to any server.

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