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 19 June 2026
Other ways to write it
| Cardinal | eighteen |
|---|---|
| Ordinal | eighteenth |
| Currency | eighteen dollars |
| Check format | Eighteen and 00/100 |
How number-to-words spelling works
A cardinal number names a quantity (eighteen), while an ordinal names a position (eighteenth). English hyphenates compound numbers from twenty-one to ninety-nine and groups digits into thousands, millions, and billions.
For house-style rules on spelling out numbers, see the Chicago Manual of Style, or read our guide to spelling numbers in words.
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 |
Try another number
Enter a number above and let the digits reveal your destiny!
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".