Superscript Two ²

The Superscript Two character (²) is a standard HTML entity defined in the HTML specification. In HTML source code, it can be written using the named entity reference ², the decimal numeric character reference ², or the hexadecimal numeric reference ². The character is assigned Unicode code point U+00B2 in the Universal Character Set.

The superscript two is the most commonly used superscript digit, representing squared values. It appears in area measurements (m²), mathematical expressions (x²), and scientific notation. The preformatted superscript character renders consistently without requiring the <sup> HTML element.

Mathematical HTML entities enable web authors to display proper mathematical notation without relying on images or specialized rendering libraries like MathJax or KaTeX. While complex equations and multi-line formulas may still benefit from dedicated math typesetting tools, individual symbols expressed as HTML entities render quickly, remain accessible to screen readers, and can be styled with CSS just like regular text content.

When deciding how to encode the Superscript Two character in your HTML documents, the named entity &sup2; is generally the most readable choice for developers reviewing or maintaining source code. The decimal form &#178; and hexadecimal form &#xB2; are equally valid alternatives that work in contexts where named entities may not be supported, or when generating HTML output programmatically from server-side code. All three representations produce identical visual output in every modern web browser.

Use the superscript two for squared measurements (km², ft²), algebraic expressions (a² + b² = c²), and chemical formulas. It is one of the few superscript digits available as a precomposed character, making it convenient for inline use in text content without additional HTML markup.