Roman Numeral Converter

A Roman numeral converter translates between modern Arabic numerals and Roman numeral notation. Romans used letters I, V, X, L, C, D, and M to represent numbers

The calculator uses the standard published formula for roman numeral. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.

The core formula is: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Each step in the calculation is shown so you can verify the result manually.