HTML Entities Cheat Sheet: Complete Reference Guide

What Are HTML Entities?

HTML entities are special text sequences that represent characters in HTML documents. They begin with an ampersand (&) and end with a semicolon (;). Entities exist because certain characters have special meaning in HTML syntax -- the less-than sign (<) opens a tag, the ampersand starts an entity reference, and the greater-than sign (>) closes a tag. Without entities, there would be no way to display these characters as literal text in an HTML document.

Beyond the syntactically reserved characters, entities also provide access to characters that may not be easily typed on a standard keyboard: mathematical symbols, currency signs, Greek letters, arrows, and thousands of other special characters from the Unicode standard.

Three Forms of HTML Entity References

Every HTML entity can be expressed in three different forms. Understanding the differences helps you choose the right approach for your situation.

Named Entity References

Named entities use a human-readable keyword between the ampersand and semicolon. For example,© renders as the copyright symbol (©), and— renders as an em dash (—). Named entities are easier to read and remember, making your source code more maintainable. However, not every Unicode character has a named entity -- only about 2,200 named entities are defined in the HTML specification, out of over 140,000 Unicode characters.

Decimal Numeric References

Decimal numeric references use the pattern &# followed by the Unicode code point in decimal and a semicolon. For example,© also renders as the copyright symbol (©). Decimal references work for any Unicode character, making them the universal fallback when a named entity does not exist. They are commonly used for emoji and CJK characters.

Hexadecimal Numeric References

Hexadecimal numeric references use &#x followed by the Unicode code point in hexadecimal. For example, ©is another way to write the copyright symbol (©). Hexadecimal references are useful when working with Unicode charts and documentation, which typically list code points in hex.

Essential HTML Entities (Must Know)

The following five entities are the ones every web developer must memorize. These characters are reserved in HTML syntax, and using them literally in your markup will cause rendering errors or, worse, security vulnerabilities.

Typographic Entities

Professional web typography relies heavily on HTML entities for proper punctuation. Using typographically correct characters instead of their ASCII approximations makes your content look polished and read more naturally. Here are the most commonly used typographic entities.

Mathematical and Technical Symbols

Developers and technical writers frequently need mathematical symbols that are not available on a standard keyboard. HTML entities provide access to the full range of mathematical operators, comparison symbols, and set theory notation.

Currency Symbols

Displaying prices and financial information requires currency symbols from around the world. While some common currency symbols appear on most keyboards, many others require entity references.

Arrow Symbols

Arrows are used extensively in user interfaces, documentation, and technical writing. HTML provides named entities for the most common directional arrows.

When to Use Named vs Numeric Entities

Choosing between named and numeric entity references is a practical decision that depends on your specific situation.

Use named entities when the entity is one of the common, well-known ones like &, <,©, or —. Named entities make your source code readable and are easier for other developers to understand during code review. They also serve as self-documenting code: seeing  instantly communicates intent, while   requires a lookup.

Use numeric references when dealing with characters that do not have named entities, when you need emoji or characters from non-Latin scripts, or when you want maximum compatibility across parsers and tools. Some older HTML processors may not recognize all named entities, but numeric references are universally supported.

Use the character directly (with UTF-8 encoding) for most non-reserved characters when your document is served with a proper charset=UTF-8 declaration. Modern browsers handle UTF-8 natively, so writing the copyright symbol directly (©) is just as valid as writing ©. The main exception is the five reserved characters listed above, which should always be encoded in HTML content contexts.

Common Mistakes to Avoid

Working with HTML entities has several common pitfalls that can lead to broken rendering or security vulnerabilities:

• Double encoding: Encoding an already-encoded string produces sequences like < which renders as the literal text "<" instead of the less-than sign. Always check whether your data is already encoded before applying encoding.
• Missing semicolons: Forgetting the trailing semicolon (&amp instead of &) can cause browsers to misinterpret the entity. While modern browsers are somewhat forgiving, always include the semicolon for reliability.
• Wrong encoding context: HTML entity encoding is for HTML content. If you need to encode data for a URL, use URL encoding (percent-encoding) instead. For JavaScript strings, use JavaScript escaping. For JSON, use JSON string escaping.
• Encoding in the wrong layer: In modern frameworks like React, JSX automatically escapes text content. Adding manual HTML encoding on top of that produces visible entity text instead of the intended characters.

Encoding in Practice

The most efficient way to work with HTML entities in practice is to use a tool that handles the encoding for you. Our HTML Entity Encoder/Decoder supports all named entities, numeric references, and includes a searchable reference table. For security-focused encoding, the XSS Prevention mode encodes based on the specific HTML context (element content, attributes, JavaScript, CSS, or URLs) following OWASP guidelines.

For more on the security implications of proper encoding, see our XSS Prevention Guide. If you work with Unicode characters beyond the basic Latin set, our guide on Unicode in HTML covers character encoding, emoji, and common pitfalls in depth.