Regex Tester
Test regular expressions with live match highlighting. Supports flags and capture groups.
How to use Regex Tester
- 1
Enter your regular expression pattern.
- 2
Toggle flags (g, i, m, s) as needed.
- 3
Type or paste your test string.
- 4
Matches are highlighted in yellow with index positions and capture groups shown.
Why use this tool?
- Live match highlighting as you type.
- Shows capture groups and match positions.
- Supports all JavaScript regex flags.
Frequently Asked Questions
Which regex flavor is used?
JavaScript (ECMAScript) regular expressions. Syntax may differ slightly from PCRE (PHP), Python, or other flavors.
What do the flags mean?
g = global (find all matches), i = case-insensitive, m = multiline (^ and $ match line boundaries), s = dotAll (. matches newlines).
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