The Downwards Two Headed 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+21A1 (decimal 8609).
Use ↡ in HTML to render ↡ on a web page.
On Windows you can type it with Alt+8609 (hold Alt and enter the number on the numeric keypad).
Yes — copying is completely free and unlimited, and works right in your browser with no sign-up.