Windows: press `Alt` + `0247` on the numeric keypad
Mac: press `Option` + `/`
Chromebook: press `Ctrl` + `Shift` + `U`, type `00F7`, then press `Enter`
iPhone/iPad: press and hold the `÷` key if available, or use the symbols keyboard
Android: open the symbols keyboard and tap `÷`
Copy and paste: `÷`