Roman numeral converter

Type a number or a Roman numeral and get the conversion with its breakdown.

How it works

Roman numerals use seven letters: I (1), V (5), X (10), L (50), C (100), D (500) and M (1000). They add up left to right, except when a smaller symbol comes before a larger one, when it’s subtracted: IV = 4, IX = 9, XL = 40, CM = 900.

Standard notation goes up to 3,999 (MMMCMXCIX).

Frequently asked questions

How do you write 2026 in Roman numerals?

MMXXVI: MM (2000) + XX (20) + VI (6).

Why can’t I write IIII?

In standard notation a symbol isn’t repeated more than three times in a row, so 4 is IV. Some clock faces use IIII by tradition.

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