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Roman Numeral Converter

Convert between numbers and Roman numerals (1-3999)

Number to Roman

MMXXIV

Roman to Number

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Reference Chart

RomanValueRomanValue
I1V5
X10L50
C100D500
M1000IV4
IX9XL40
XC90CD400
CM900

Roman Numeral Rules

Roman numerals use seven symbols: I, V, X, L, C, D, M. When a smaller numeral appears before a larger one, it's subtracted (IV=4). When it appears after, it's added (VI=6). A numeral can be repeated up to 3 times (III=3, but 4=IV).

Frequently Asked Questions

What are the basic Roman numerals?
I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Subtractive: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900.
What is the largest Roman numeral?
Standard system: 3999 (MMMCMXCIX). Vinculum notation extends beyond by placing a bar over letters.
Why is 4 written as IV?
Subtractive notation: IV means 5-1=4. It's more compact than IIII (though IIII appears on some clock faces).