Roman numeral converter

Convert whole numbers and Roman numerals in either direction.

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Direction

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Understand the subtractive pairs

I before V or X subtracts one. X before L or C subtracts ten. C before D or M subtracts one hundred. Other symbols add their values. The breakdown follows the same pairs.

Next: Scientific notation converter

Worked example

944 becomes CMXLIV: CM is 900, XL is 40, and IV is 4. Together they add to 944.

Next: Binary translator

Before you rely on the result

This tool accepts the standard forms from 1 through 3999. Zero, negative numbers, fractions, overlines and nonstandard forms such as IIX are not included.

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