Regex Tester

Test and visualize regex patterns with real-time highlighting

Free online regex tester to test and debug regular expressions in real-time. See all matches highlighted instantly. Supports JavaScript regex with g, i, m, s, u flags. Extract capture groups, count matches. Perfect for email validation, URL matching, data cleaning, and log parsing. 100% client-side, no data transmission.

Regex Pattern

Enter a valid JavaScript regex pattern

Test String

What Is a Regex Tester?

A Regex Tester (Regular Expression Tester) lets you write, test, and debug regex patterns against sample text in real-time. As you type your pattern, matches are instantly highlighted in the test string, and all matched groups are listed below. This tool uses the JavaScript regex engine, making it perfect for testing patterns used in Node.js, React, Angular, and browser-based applications.

Supported Regex Flags

g – Global (find all)

i – Case insensitive

m – Multiline

s – Dot matches newline

u – Unicode

Common Regex Patterns

\b\w+@\w+\.\w+\bMatch email addresses

https?://\S+Match URLs

^\d{{4}}[-/]\d{{2}}[-/]\d{{2}}Match dates (YYYY-MM-DD)

\b\d{{1,3}}\.\d{{1,3}}\.\d{{1,3}}\.\d{{1,3}}\bMatch IPv4 addresses

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