Regex Tester

Test regular expressions with real-time matching and highlighting. Supports JavaScript regex flags, capture groups, and match details. Free, no signup.

Regular Expression

//g

Test String

Match Highlighting2 matches

Capture Groups

Match 1"hello@example.com"index 14

Group 1: "hello"Group 2: "example.com"

Match 2"support@toolcascade.com"index 35

Group 1: "support"Group 2: "toolcascade.com"

About this tool

Regular expressions are powerful pattern-matching sequences used across virtually every programming language. This Regex Tester lets you write patterns and see matches highlighted in real time, so you can iterate quickly without switching between a code editor and documentation.

All matching uses the browser's native JavaScript RegExp engine. Your patterns and test strings never leave your device, making it safe to test against sensitive data. Toggle flags to change matching behavior — global (g) finds all occurrences, case-insensitive (i) ignores letter casing, and multiline (m) treats each line as a separate start/end boundary.

tuneFlags

GlobalFind all matches

Case InsensitiveIgnore letter case

Multiline^ and $ match line boundaries

infoMatch Summary

Total Matches2

Flagsg

StatusValid

lightbulbQuick Reference

. — Any character
\d — Digit [0-9]
\w — Word character
\s — Whitespace
^ — Start of string
$ — End of string
* — 0 or more
+ — 1 or more
? — 0 or 1

Frequently Asked Questions

What regex flags are supported?

This tool supports all JavaScript regex flags: g (global), i (case-insensitive), m (multiline), s (dotAll), u (unicode), and y (sticky). Toggle them on or off to change matching behavior.

Does it show capture groups?

Yes. When your regex contains capture groups (parentheses), the tool displays each group's match separately along with its index position in the test string.

Is my regex data private?

Yes. All regex matching runs entirely in your browser using JavaScript's native RegExp engine. No data is sent to any server.

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