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Roman Numerals Converter

Convert between Roman numerals and Arabic numerals

How to use the Roman numeral converter

This converter both lets you convert arabic numerals to roman numerals, and vice versa. Type in a number in the field you'd like to convert from, and it will show in the other format in the other field. The converter only allows integers between 1 and 3999.

For further details on how to convert roman numerals, please visit our website dedicated to this:

About Roman Numerals:

Roman Numerals originates, as suggested by their name, from Ancient Rome. The system is based on adding together predefined values. The following symbols are used:

In order to write for instance 623 in Roman numerals you write DCXXIII, i.e. 500+100+10+10+1+1+1. For the numbers 4 and 9, however, subtraction is used instead of addition, and you then write the smaller value in front of the greater. For example, to write 14 as XIV, i.e. 10+5-1, and 299 is written as CCXCIX, i.e. 100+100+100-10+10-1. The number 299 would also be possible to write as CCIC, but according to the strict defition you're only allowed to subtract numbers that are one order of magnitude smaller than the number you're subtracting from, and therefore IC for 99 is incorrect.

Roman numerals are commonly used in numbered lists, and in titles of monarchs, such as King Louis XIV of France.