Roman numeral converter
Convert numbers and Roman numerals in either direction, with a breakdown of additive and subtractive symbols.
How it works & useful details
How it works & limits
Supports canonical Roman numerals from I (1) to MMMCMXCIX (3,999). Uppercase and lowercase input are accepted; output is uppercase. Subtractive pairs are IV, IX, XL, XC, CD, and CM.
Nonstandard spellings such as IIII, IC, or VX are rejected. Zero, negative numbers, fractions, and overbar notation are outside this tool's scope.
Your working space
Change the values to explore the preview. Use the action below to create a copyable, downloadable result. All calculations stay on this device; refreshing clears your work.
