The Left Right Double Arrow symbol (⇔). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Arrows.
The quickest way is to copy ⇔ from this page and paste it anywhere. You can also insert it with its Unicode, HTML, or alt code listed above.
⇔ is U+21D4 (decimal 8660).
Use ⇔ in HTML to render ⇔ on a web page.
On Windows you can type it with Alt+8660 (hold Alt and enter the number on the numeric keypad).
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