HTML Character Entities Encoder/Decoder

Escaping depends on context. In ordinary HTML text, ampersand and less-than need encoding when they could start a reference or tag; greater-than is usually optional. In an attribute, encode the quote that delimits the value as well. Safe handling of untrusted content requires context-specific encoding, not one universal five-character replacement.

A named reference uses a label such as ©. Decimal and hexadecimal numeric references use the character's code point, such as © and ©. HTML defines thousands of named references, often with aliases. Numeric references can represent Unicode scalar values, but invalid values such as surrogate code points are replaced during parsing.

' is predefined in XML and supported in modern HTML, but it was not a named reference in HTML 4. Use ' when output must remain compatible with an HTML 4 consumer. XML and XHTML parsers support ' when the input is valid XML.

HTML defines thousands of named character references, and several names can map to the same character. This calculator includes a smaller curated table and uses numeric references when no included name exists. Numeric references cover valid Unicode scalar values; surrogate code points are not valid characters.

Use 'Encode all' when you need maximum compatibility with consumers that cannot be trusted to handle UTF-8, such as RSS or Atom feeds read by older aggregators, plain-text email pipelines that downgrade to ASCII, legacy CMS templates, or character-set-confused log parsers. It escapes every non-ASCII character plus the reserved 5, so the output is pure 7-bit ASCII and survives any encoding-mangling step in transit. For normal modern web pages that already declare UTF-8 in their charset, 'Encode (safe)' is enough and keeps the source readable.