Regex Tester & Explainer

Test regular expressions with real-time match highlighting, named groups, and plain-English explanation of each part.

Free Always No Account Needed 100% Client-Side
//
flags: /g/
2 matches
Contact us at hello@example.com or support@editingtools.tech for help.
#MatchStartEndGroups
1hello@example.com1431#1: hello#2: example.com
2support@editingtools.tech3560#1: support#2: editingtools.tech

About this tool

Regular expressions are powerful patterns for matching, searching, and manipulating text. Writing and debugging them can be tricky — this tool makes it visual and interactive.

Paste your regex and test string, and matches are highlighted in real-time. The tool shows every match, capture group, and named group in a structured table. Hover over any match to see its exact position (start/end index).

The explanation panel breaks down each token in your regex into plain English — for example, \d{3}-\d{4} is explained as "exactly 3 digits, a literal hyphen, exactly 4 digits".

Supports all JavaScript regex flags: g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), and d (indices).

Frequently Asked Questions

What regex flavor does this use?
JavaScript (ECMAScript) regex, which is compatible with most modern programming languages and supported natively in browsers.
How do I use named capture groups?
Use the syntax (?<name>pattern). For example, (?<year>\d{4}) creates a group named 'year'.
What does the 's' flag do?
The 's' (dotAll) flag makes '.' match newline characters as well, which it doesn't by default.
How do I match a literal dot?
Escape it with a backslash: \. — without the backslash, '.' matches any character.

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