18 in Roman Numerals
18 written in Roman numeralsXVIII
18 = XVIII. Read left to right: X (10) + V (5) + III (3) = 18.
Going the other way, the Roman numeral XVIII equals the number 18.
How to write 18 in Roman numerals
- Tens: 10 is X.
- Ones: 8 is VIII.
- Put them together, largest first: X + VIII = XVIII.
XVIII uses only additive notation: every symbol is the same size or smaller than the one before it, so you simply add them up.
18 is an even number and written with 5 symbols in Roman numerals.
Where you might see XVIII
- In dates written in Roman numerals, XVIII can stand for day 18 of the month.
- Super Bowl XVIII was the 18th Super Bowl, played in early 1984.
- Book chapters, outlines, movie sequels and royal names use numerals like XVIII for the number 18.
Multiples of XVIII
| Sum | Number | Roman numeral |
|---|---|---|
| 18 × 2 | 36 | XXXVI |
| 18 × 3 | 54 | LIV |
| 18 × 5 | 90 | XC |
| 18 × 10 | 180 | CLXXX |
Numerals near XVIII
| Number | Roman numeral |
|---|---|
| 13 | XIII |
| 14 | XIV |
| 15 | XV |
| 16 | XVI |
| 17 | XVII |
| 18 | XVIII |
| 19 | XIX |
| 20 | XX |
| 21 | XXI |
| 22 | XXII |
| 23 | XXIII |
Questions
How do you write 18 in Roman numerals?
18 is written XVIII.
What number is XVIII?
XVIII is 18.