Regex Tester Online — Test Regular Expressions Free

Updated July 2026 · 2 min read

Build and test regular expressions (regex) instantly. Enter a pattern and test string to see matches highlighted in real time. Supports global (g), case-insensitive (i), multiline (m), and dotall (s) flags. Perfect for developers, data analysts, and SEO professionals. Free, no signup.

Test Regex Now →

How to Use the Regex Tester

Open the Regex Tester
Type your regex pattern in the pattern field
Paste your test string and see matches highlighted instantly

Supported Regex Features

Character classes — \d, \w, \s, [abc]
Quantifiers — +, *, ?, {n,m}
Groups & captures — (group), (?:non-capturing)
Lookahead & lookbehind — (?=...), (?<=...)
Anchors & boundaries — ^, $, \b

FAQ

What regex flavor is supported?: JavaScript (ECMAScript) regex. Compatible with most modern programming languages.
Can I save my regex patterns?: The tester runs in your browser. Bookmark the page to keep your working patterns handy.
Is there a regex reference or cheat sheet?: Yes — common patterns and syntax are displayed in the sidebar for quick reference.

👉 Start testing regex patterns →

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