Regex Tester

Free Online Regex Tester

Test JavaScript regular expressions with real-time match highlighting and capture group extraction. Type your pattern and test string — matches are highlighted instantly as you type.

Features

• Real-time highlighting — matches highlight as you type, no submit button needed
• Capture groups — see each group extracted from every match
• All JS flags — global, case-insensitive, multiline, dotAll, unicode
• Pattern library — common patterns for email, URL, phone, date, IP, hex colors, HTML tags, and passwords
• Match details — index positions and group values for each match

JavaScript Regex Syntax

This tool uses JavaScript's native RegExp engine. Key differences from other flavors: use \d for digits, \w for word characters, (?=...) for lookahead, (?<=...) for lookbehind (ES2018+), and (?<name>...) for named groups.

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