| Decimal | 40 |
| Binary | 101000 |
| Hexadecimal | 0x28 |
| Roman | XL |
| Square root of | 1600 |
| Factors | 5 2 2 2 |
| English | forty |
| Wikipedia article about 40 | Article about 40 |
| ASCII code for | Open parenthesis (or open bracket) |
| random from 0 to 6 | Show |
| random from 0 to 10 | Show |
| random from 0 to 100 | Show |
| random from 0 to 1000 | Show |