Roman Numeral Converter
Convert integers 1–3999 to Roman numerals or interpret Roman-letter input as an integer.
How to use
- Enter an integer or a Roman numeral and run.
Capabilities and scope
If the input contains only IVXLCDM letters, it is greedily consumed from largest symbols; otherwise a 1–3999 integer is encoded using subtractive pairs.
How it works
A table ordered M,CM,D,CD,C,XC,L,XL,X,IX,V,IV,I drives both encoding and decoding.
Example
1994 becomes MCMXCIV.
Useful for
- Quickly check common Roman numeral and integer forms
Before you use it
- Decoding is not a strict canonical-notation validator and can accept some nonstandard repetitions such as IIII.
Frequently asked questions
Can zero be encoded?
No. Numeric input must be an integer from 1 through 3999.