What is URL Encoding?

URL encoding (percent-encoding) replaces characters that are unsafe or reserved in URLs with a percent sign followed by their hex code — for example a space becomes %20. It ensures URLs remain valid and unambiguous.

It is essential for query string values, which may contain spaces, ampersands, or non-ASCII characters that would otherwise break the URL.

Key points

  • Replaces unsafe characters with % followed by their hex code.
  • A space becomes %20 (or + in form-encoded data).
  • Reserved characters like &, ? and = must be encoded inside values.
  • Required for non-ASCII characters in URLs.

Example

hello world & co
→ hello%20world%20%26%20co

Common uses

  • Encoding query-string parameter values
  • Building safe links programmatically
  • Submitting HTML form data
  • Passing data in URLs without breaking them

Work with URL Encoding directly in your browser.

Open the URL Encoder/Decoder

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