Free online tool

Roman Numeral Converter

Convert in either direction and validate canonical subtractive notation.

Converted valueMMXXVI

Roman numeral symbols

I = 1V = 5X = 10L = 50C = 100D = 500M = 1000

Method

Roman numeral notation

The converter uses modern canonical subtractive notation for integers from 1 through 3,999. It validates the result by converting back to canonical form.

Historical Roman usage was not fully standardized, so inscriptions and clocks may use variants such as IIII instead of IV.

Questions

Roman Numeral Converter FAQ

What numbers can standard Roman numerals represent?

The common modern system represented here covers integers from 1 through 3,999 using I, V, X, L, C, D, and M.

Why is 4 written IV instead of IIII?

Modern canonical notation commonly uses subtractive pairs: IV for 4, IX for 9, XL for 40, XC for 90, CD for 400, and CM for 900.

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