18 in Words
How do you write 18 in words?
The number 18 is written eighteen in words. As an ordinal it is eighteenth, and on a check you would write Eighteen and 00/100.
Last updated 24 August 2026
Other ways to write it
| Cardinal | eighteen |
|---|---|
| Ordinal | eighteenth |
| Currency | eighteen dollars |
| Check format | Eighteen and 00/100 |
How 18 is written
18 is the sum of its place values, 10 + 8, and is written eighteen.
Its ordinal form is eighteenth — only the final element takes the ordinal ending — and on a check the amount line reads "Eighteen and 00/100", where 00/100 stands for zero cents.
The last part is not built from its digits: English names 10 to 19 with single irregular words, so this is eighteen, never ten eight.
For house-style rules on spelling out numbers, see the Chicago Manual of Style.
Facts about 18
- 18 is an even number.
- It is not a prime number.
- Digit sum: 9.
- Roman numerals: XVIII.
- Binary: 10010.
- Hexadecimal: 12.
| Digit | Place |
|---|---|
| 1 | tens |
| 8 | ones |
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Frequently asked questions
How do you write 18 in words?
18 in words is "eighteen".
How do you spell 18?
18 is spelled "eighteen".
How do you write 18 on a check?
On a check, write "Eighteen and 00/100".