Roman numerals converter

Type an ordinary or a Roman number: the tool works out which way to convert.

Number or Roman numeral

Roman numeralMMXXVI

M = 1000

X = 10

V = 5

I = 1

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Calculator by Kalkio · kalkio.app

The rules

I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1000. Symbols are added from the largest, and a smaller symbol before a larger one means subtraction: IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900. The same symbol appears at most three times in a row.

Result

The rules

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