The Box Drawings Light Diagonal Upper Left To Lower Right symbol (╲). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Box Drawing.
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+2572 (decimal 9586).
Use ╲ in HTML to render ╲ on a web page.
On Windows you can type it with Alt+9586 (hold Alt and enter the number on the numeric keypad).
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