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URL Encoder/Decoder: Handling Special Characters in URLs

Learn why URL encoding is necessary, which characters need encoding, and how to properly encode URLs for web applications.

2025-01-034 min

What is URL Encoding?

URL encoding converts characters into a format that can be transmitted over the Internet. Special characters are replaced with a % followed by two hexadecimal digits.

Why URL Encoding is Needed

URLs can only contain certain characters from the ASCII set. Other characters must be encoded:

Reserved Characters

These have special meanings in URLs:

  • ? - Query string separator
  • & - Parameter separator
  • = - Key-value separator
  • # - Fragment identifier

    • Unsafe Characters

    Must be encoded when used in data:

  • Spaces become %20 or +
  • @ becomes %40
  • # becomes %23

    • Common Encoding Examples

    CharacterEncoded
    Space%20
    !%21
    #%23
    $%24
    &%26
    +%2B
    =%3D
    ?%3F
    @%40

    When to Encode

    Do Encode

  • Query string values
  • Path segments with special characters
  • Form data
  • User-generated content

    • Don't Encode

  • The protocol (https://)
  • Domain names
  • Standard path separators (/)
  • Already-encoded characters

    • Our URL Encoder Tool

  • Encode and decode URLs
  • Real-time conversion
  • Full Unicode support
  • Common character reference
  • Copy result to clipboard