HTML & URL Encoding Reference

Common HTML entities and URL-encoded characters that you frequently need when developing web applications.

Character Converter

Notes

HTML Entities

• Named entities start with & and end with ; (e.g., &)
• Numeric entities start with &# and end with ; (e.g., &)
• Some characters have multiple valid representations in HTML5
• Named entities can improve code readability by being more descriptive

URL Encoding

• Also known as percent-encoding
• Reserved characters must be encoded when used in certain URL components
• Unreserved characters (A-Z, a-z, 0-9, -, _, ., ~, ’) should not be encoded
• Multi-byte characters (like €) are encoded as multiple percent-encoded bytes

References

HTML Entities

• HTML Living Standard - Named Character References
• HTML5 Named Character References
• HTML Numeric Character References

URL Encoding

• RFC 3986 - Uniform Resource Identifier (URI): Generic Syntax
  • Section 2.2: Reserved Characters
  • Section 2.3: Unreserved Characters
• URL Living Standard - Percent-encoding