Regex Tester & Debugger

Test and debug regular expressions with live match highlighting and capture group extraction.

/
/g
Examples:

Common Regex Cheat Sheet & Patterns

Use CaseRegex PatternDescription
Email Address^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$Standard email format validation
URL Formathttps?:\/\/(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\bMatches HTTP & HTTPS URLs
IPv4 Address^(?:[0-9]{1,3}\.){3}[0-9]{1,3}$Matches standard IPv4 addresses
UUID (v4/v7)^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{4}-[0-9a-fA-F]{12}$36-character hyphenated UUID pattern

Frequently Asked Questions

What is a Regular Expression (Regex)?

A Regular Expression (Regex) is a sequence of characters that forms a search pattern used for text matching, string validation, searching, and replacing operations in programming languages.

What do the regex flags (g, i, m, s, u, y) mean?

Flags modify pattern matching behavior: "g" performs global matching across the whole string, "i" makes matching case-insensitive, "m" enables multiline anchors (^ and $ match line boundaries), and "s" allows the dot (.) to match newlines.

How can I test regex matching via API?

You can query Yurlie API endpoint POST https://api.yurlie.app/v1/developer/regex passing a pattern and input text to test matches programmatically.