Work out roman numeral to number instantly with clear inputs, formula shown and shareable results.
Roman numerals add symbol values left to right, except that a smaller symbol before a larger one is subtracted. So MCMXCIV is 1000 + (1000 − 100) + (100 − 10) + (5 − 1) = 1994.
Subtractive pairs
IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900
1994.
The system is purely additive and positional-free, so it never needed a placeholder digit; zero entered European mathematics much later.