Regex Examples for Developers

Long-tail regex reference pages with real examples and quick test links.

This hub collects practical regex patterns developers frequently search for, including email validation, phone number checks, URL structure matching, IPv4 validation, and password complexity patterns. Each example page explains what the pattern does, where it can fail, and how to test it quickly in the Regex Tester workspace. Use these pages as starting points, then refine patterns to fit your application rules.

Email Regex Example

Validate common email-like strings with a practical pattern suitable for frontend form checks.

/^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,}$/i

Phone Number Regex Example

Match normalized phone numbers with optional plus prefix and 7 to 15 digits.

/^\+?[0-9]{7,15}$/

Password Regex Example

Require uppercase, lowercase, number, symbol, and a minimum length for strong-password policies.

/^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[^A-Za-z0-9]).{10,64}$/

URL Regex Example

Validate common HTTP/HTTPS URLs including optional ports, paths, and query fragments.

/^https?:\/\/[A-Za-z0-9.-]+(?:\:[0-9]{2,5})?(?:\/[\w\-.~:/?#[\]@!$&'()*+,;=%]*)?$/i

IPv4 Regex Example

Match IPv4 addresses with strict 0-255 octet validation for each of four segments.

/^(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)(\.(25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)){3}$/

Related developer pages

Regex Tester & Generator for interactive testing, Base64 vs Hex guide for encoding comparisons, and Text Diff Checker for content review workflows.