How do you write 18 in Roman numerals?

18 is written as XVIII in Roman numerals: 18 = 10 (X) + 8 (VIII). The symbols are then written from largest to smallest value.

What does XVIII stand for?

XVIII stands for the number 18. Reading left to right: X = 10, VIII = 8.

How do you write "18th" in Roman numerals?

Ordinal numbers use the same numerals as cardinal numbers, so "18th" is written XVIII — Roman notation has no separate ordinal form.

18 in Roman Numerals

How to write the number 18 in Roman numerals, with the full place-value breakdown.

The number 18 in Roman numerals

XVIII

Place-value breakdown

18 = 10 + 8, so XVIII = X + VIII. Roman numerals are written from largest to smallest value, left to right:

Place	Value	Roman	Rule
Tens	10	X	Additive rule: X = 10 (symbols are simply added)
Ones	8	VIII	Additive rule: VIII = 8 (symbols are simply added)

About the number 18

The number 18 is written XVIII in Roman numerals.

Looking for the ordinal form — "18th in Roman numerals"? Roman notation makes no distinction between cardinal and ordinal numbers, so "18th" is also written XVIII.

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