Regex Tools

Build, test, and understand regular expressions

Regex is powerful and famously easy to get subtly wrong. These tools handle the everyday regex work — testing, explaining, and reusing patterns — entirely in your browser.

Regex Tester

Test a pattern against sample text with live match highlighting and capture groups.

Regex Replace

Find and replace text using a regular expression, with backreferences.

Regex Explainer

Break down a regex pattern into plain-English tokens.

Common Patterns Library

Copy-ready regex patterns for email, URL, IPv4, and more.