Regex tester

Test JavaScript regular expressions live with match highlighting, capture groups, named groups and find-and-replace.

Pattern

Flagsgglobalicase insensitivemmultilinesdotAlluunicodeysticky

Input

Matches — 0 match

Enter a pattern and some text to see matches.

Replacement ($1, $2, $<name>)

Replaced text

Enter a pattern and some text to see matches.

Features

Live match highlighting with numbered and named capture groups for JavaScript RegExp.
Full flag support (g, i, m, s, u, y) plus a find-and-replace preview with substitution patterns.
Test and debug patterns entirely in your browser — instant feedback, nothing uploaded.

How it works

Type a JavaScript regular expression and toggle the flags you need — global, ignore-case, multiline, dotAll, unicode or sticky.
Paste your test text below; matches are highlighted live and capture groups are listed.
Add a replacement string to preview the substituted output, then copy the result.

Your files never leave this page

Every conversion runs entirely in your browser using WebAssembly. There is no upload, no server-side processing, no analytics, and no cookies. Open DevTools → Network during the operation and you will see zero outbound traffic.

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Topics covered

regex tester online
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