How to Convert to or from Roman Numerals

Enter any number between 1 and 3999 into the Number field. The calculator will convert the number into a Roman numeral.

You can also enter Roman numerals (letters M, D, C, L, X, V, and I) into the Roman Numerals field. The calculator will convert it into a standard (Arabic) number.

Image of roman numerals
How to Write and Count Roman Numerals
Roman numerals consist of the letters I, V, X, L, C, D, and M, representing 1, 5, 10, 50, 100, 500, and 1000.
The Colosseum in Rome lit up with warm lights against a deep blue evening sky.
The Roman Calendar
This is the predecessor to our modern calendar. Some of its features are still in use today.