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RegexKit / Patterns

Common regex patterns

Tested patterns for the things developers validate every week. Each page shows what passes, what fails, the caveats, and code for JavaScript and Python.

  • Email address^[A-Za-z0-9._%+-]+@[A-Za-z0-9-]+(?:\.[A-Za-z0-9-]+)*\.[A-Za-…
  • Phone number^(?:\+?1[-. ]?)?\(?([2-9][0-9]{2})\)?[-. ]?([2-9][0-9]{2})[-…
  • URL^https?:\/\/(?:[A-Za-z0-9-]+\.)+[A-Za-z]{2,}(?::\d{2,5})?(?:…
  • IPv4 address^(?:(?:25[0-5]|2[0-4]\d|1\d\d|[1-9]?\d)\.){3}(?:25[0-5]|2[0-…
  • Date (YYYY-MM-DD)^(\d{4})-(0[1-9]|1[0-2])-(0[1-9]|[12]\d|3[01])$
  • Time (24-hour)^([01]\d|2[0-3]):([0-5]\d)(?::([0-5]\d))?$
  • UUID^[0-9a-f]{8}-[0-9a-f]{4}-[1-8][0-9a-f]{3}-[89ab][0-9a-f]{3}-…
  • Hex colour^#(?:[0-9a-fA-F]{3,4}|[0-9a-fA-F]{6}|[0-9a-fA-F]{8})$
  • Strong password^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[^A-Za-z0-9]).{12,}$
  • ZIP / postal code^\d{5}(?:-\d{4})?$
  • URL slug^[a-z0-9]+(?:-[a-z0-9]+)*$
  • HTML tag<\/?([a-zA-Z][a-zA-Z0-9-]*)\b[^>]*>
  • Credit card number^(?:4\d{12}(?:\d{3})?|5[1-5]\d{14}|2(?:2[2-9][1-9]|2[3-9]\d|…
  • Extra whitespace[ \t]{2,}

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Regex

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  • Visual regex builder
  • Regex generator (AI)
  • Regex cheat sheet
  • Common patterns
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  • Python regex
  • JavaScript regex

Encode & hash

  • Base64 encode / decode
  • URL encode / decode
  • Hash generator
  • JWT decoder
  • HTML entities

Text & data

  • Diff checker
  • JSON formatter
  • Case converter
  • UUID generator
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