The Upper Right Drop-Shadowed White Square symbol (❐). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Dingbats.
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+2750 (decimal 10064).
Use ❐ in HTML to render ❐ on a web page.
On Windows you can type it with Alt+10064 (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.