Roman Numeral Converter
Convert between Roman numerals and Arabic (decimal) numbers. Roman numerals use letters I, V, X, L, C, D, and M to represent values. They are still used today in clocks, book chapters, movie sequels, and formal documents. Supports numbers from 1 to 3999.
Convert Decimal to Roman Numeral
Roman Numeral Reference
I
1
V
5
X
10
L
50
C
100
D
500
M
1000
Common Conversions
4
IV
9
IX
40
XL
90
XC
400
CD
900
CM
1999
MCMXCIX
2024
MMXXIV
Rules
Subtractive notation: A smaller numeral before a larger one means subtraction.
- IV = 4 (5 - 1)
- IX = 9 (10 - 1)
- XL = 40 (50 - 10)
- XC = 90 (100 - 10)
- CD = 400 (500 - 100)
- CM = 900 (1000 - 100)
Range: Standard Roman numerals represent numbers from 1 to 3,999.
FAQ
What are the basic Roman numeral values?
I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Numbers are formed by combining these symbols, adding when smaller follows larger (VI=6) or subtracting when smaller precedes larger (IV=4).
Why can this tool only convert up to 3999?
Standard Roman numerals have no symbol for 5000 or higher. Numbers above 3999 require special notation like overbars (a line above a numeral multiplies it by 1000), which is not universally standardized.
Where are Roman numerals still used today?
Roman numerals appear in clock faces, Super Bowl numbering, movie sequel titles, book chapter numbers, monarchs names (Queen Elizabeth II), and copyright years in movie credits.