Test these patterns instantly in the Regex Tester.Open Regex Tool →

Regex Recipes

Common, production-ready regex patterns you can reuse across projects.

Common Patterns

Key / CodeDescription
Email^[\w-\.]+@([\w-]+\.)+[\w-]{2,4}$
URLhttps?:\/\/[\w.-]+(?:\/[\w./?%&=-]*)?
IPv4^(?:\d{1,3}\.){3}\d{1,3}$
UUID v4^[0-9a-fA-F]{8}-[0-9a-fA-F]{4}-4[0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}$
ISO Date^\d{4}-\d{2}-\d{2}$
Hex Color^#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3})$

Text Utilities

Key / CodeDescription
Slug^[a-z0-9]+(?:-[a-z0-9]+)*$
SemVer^\d+\.\d+\.\d+(-[0-9A-Za-z.-]+)?$
Base64^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$

Tips

Regex is context-sensitive. Always validate against your inputs and consider escaping for your runtime (JS, Python, Go).

Knowledge is power.