Roman Numeral Rules
Basic Symbols
Roman numerals use the following symbols:
I - 1
V - 5
X - 10
L - 50
C - 100
D - 500
M - 1000
Composition Rules
Repeat the same symbol:
Smaller on the right of larger:
Smaller on the left of larger:
Subtraction only for:
Common Examples
Table Columns
- Arabic number
- Roman numeral
Example Rows
1 - I
4 - IV
9 - IX
40 - XL
90 - XC
400 - CD
900 - CM
1999 - MCMXCIX
FAQ
Are the results accurate?
This tool follows common calculation rules. For formal or business scenarios, please verify with your actual rules.
Will my input be uploaded?
No. Processing is performed locally in your browser by default.