ローマ数字コンバーター
Convert between numbers and Roman numerals instantly.
Roman Numeral Reference
I = 1
V = 5
X = 10
L = 50
C = 100
D = 500
M = 1,000
Subtractive notation: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900
A smaller numeral before a larger one means subtraction. Otherwise, add the values left to right.
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