Web Dev Helpers

Regex Tester

Test JavaScript regex patterns with flags and live highlighting.

Pattern

//

Test string

Matches (1)

  1. [12] contact@suparnpatra.comgroups: ["contact", "suparnpatra.com"]

Replace

Reach me at [email].

About this tool

Type a pattern and a test string, see matches highlighted in real time. Toggle flags (g, i, m, s, u, y), see capture groups, and test replacements.

FAQs

What regex flavour is this?

JavaScript / ECMAScript regex (the same flavour you'd write in `.match()` or `.replace()`).

What does the 'u' flag do?

Turns on Unicode mode - lets you use \u{...} escapes and treats surrogate pairs as a single character.

How do I match newlines?

Use the 's' flag (dotAll) so '.' matches newlines, or use [\s\S] which works regardless of flags.

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