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About this tool
Convert between Roman numerals and decimal numbers, using the subtractive notation for 4, 9, 40, 90, 400 and 900. It covers 1 to 3999, which is the range the plain notation reaches without an overline.Questions
- Why does it stop at 3999?
- Standard Roman notation has no zero and no way to write larger numbers without an overline or a different convention. 3999 is MMMCMXCIX, the largest value the plain form expresses.