Left Right Arrow ↔

The Left Right Arrow character (↔) is a standard HTML entity defined in the HTML specification. In HTML source code, it can be written using the named entity reference ↔, the decimal numeric character reference ↔, or the hexadecimal numeric reference ↔. The character is assigned Unicode code point U+2194 in the Universal Character Set.

The left-right arrow (bidirectional arrow) points in both directions simultaneously. It is used in mathematics to denote bijective functions, logical biconditionals, and reversible chemical reactions. In UI design, it can indicate resizable areas or bidirectional relationships.

Arrow entities serve as directional indicators in navigation interfaces, mathematical expressions, flowcharts, and textual content throughout the web. Because they render as scalable text characters rather than bitmap images, HTML arrow entities are resolution-independent, styleable with CSS properties like color and font-size, and fully accessible to assistive technologies including screen readers.

When deciding how to encode the Left Right Arrow character in your HTML documents, the named entity ↔ is generally the most readable choice for developers reviewing or maintaining source code. The decimal form ↔ and hexadecimal form ↔ 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 bidirectional arrow to indicate two-way relationships, logical equivalence (if and only if), chemical equilibrium, and resizable UI elements. It communicates that an operation or relationship works in both directions, which a single directional arrow cannot express.