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Left Right Double Arrow HTML entity ⇔
⇔ is the HTML entity for Left Right Double Arrow ⇔ (U+21D4). Copy ⇔, ⇔ and the CSS, JavaScript, Python and URL escapes.
- Entity
⇔- Also written
⇔⇔⇔- Code point
- U+21D4
- Unicode name
- LEFT RIGHT DOUBLE ARROW
- Block
- Arrows
- Category
- Math symbol (Sm)
- Since
- Unicode 1.1
- Defined in
- HTML 4.01 and HTML5
Codes to copy
| HTML named | ⇔Works in HTML; in XML only & < > " ' are predefined. | |
|---|---|---|
| HTML decimal | ⇔Works in HTML and XML. | |
| HTML hex | ⇔Works in HTML and XML. | |
| CSS | content: "\21D4";In a stylesheet, for ::before and ::after. | |
| JavaScript | "\u21D4"Also valid in JSON. | |
| Python | "\u21d4"Python 3 string literal. | |
| Python by name | "\N{LEFT RIGHT DOUBLE ARROW}"Readable alternative using the Unicode name. | |
| URL | %E2%87%94Percent-encoded UTF-8 bytes, for a path or query value. | |
| UTF-8 bytes | E2 87 943 bytes. | |
| UTF-16 | 21D41 code unit, which is what JavaScript length counts. |
When to use it
The double two-headed arrow means 'if and only if' (logical equivalence). ⇔ is an alias that reads well in maths source.
The name dates from HTML 4, so it works in every browser and in old email clients.
More arrows
⇖North West Double Arrow⇒Right Double Arrow⇗North East Double Arrow⇑Upwards Double Arrow⇘South East Double Arrow⇐Left Double Arrow⇙South West Double Arrow⇏Rightwards Double Arrow with Stroke
All arrows · Every HTML entity · Encode or decode text
Source: the WHATWG HTML Standard list of named character references and the Unicode Character Database (Unicode 18.0).