Roman Numeral Converter
Enter a whole number from 1 to 3999 and get its standard Roman numeral, built from I, V, X, L, C, D, and M with the subtractive notation that makes 4 into IV and 9 into IX.
Standard subtractive form
The converter uses the modern rule where a smaller symbol before a larger one subtracts — so 40 is XL and 900 is CM, never XXXX or DCCCC.
Range 1 to 3999
Roman numerals have no zero and no standard symbol above 3999, so the converter accepts whole numbers in that range only.
What are Roman numerals?
A letter-based number system from ancient Rome
Roman numerals are a number system from ancient Rome that writes values with seven letters: I (1), V (5), X (10), L (50), C (100), D (500), and M (1000). Numbers are built by placing symbols from largest to smallest and adding them, with a subtractive shortcut for values like 4 and 9. They still appear on clocks, book chapters, film credits, and monarch names.
Enter a number from 1 to 3999 to see its Roman numeral, ready to copy into a title, a clock face, or a tattoo design.
Work through the symbol values from largest to smallest, writing each one as many times as it fits and subtracting its value each time.
M=1000 D=500 C=100 L=50 X=10 V=5 I=1Take 2026. Two thousands give MM, then twenty is XX, five is V, and one is I, so 2026 is MMXXVI. The subtractive rule kicks in near 4s and 9s: instead of repeating a symbol four times, you put a smaller symbol in front of a larger one — 4 is IV (one before five), 9 is IX, 40 is XL, 90 is XC, 400 is CD, and 900 is CM. That is why 1994 is MCMXCIV, not MDCCCCLXXXXIIII.
Read a Roman numeral from left to right, adding each symbol's value — unless a smaller symbol sits before a larger one, in which case you subtract it first. In MMXXVI that is 1000 + 1000 + 10 + 10 + 5 + 1 = 2026, and in MCMXCIV it is 1000 + (1000 − 100) + (100 − 10) + (5 − 1) = 1994. A few rules keep the form standard: a symbol is never repeated more than three times in a row, and only I, X, and C are used subtractively (before the next two larger symbols), so 49 is XLIX rather than IL. Because there is no symbol for zero and nothing standard beyond 3999, very large numbers and decimals cannot be written this way — which is exactly why the converter limits the input to whole numbers from 1 to 3999.
Roman numerals are exact within their range, but the notation has firm edges.
No zero, no fractions, and a 3999 ceiling
This converter uses the standard subtractive notation and accepts whole numbers from 1 to 3999 only. There is no Roman symbol for zero or for fractions, and values of 4000 and above need a vinculum (a bar over a symbol to multiply it by 1000), which is not part of everyday usage and is not produced here. Historical inscriptions sometimes used additive forms such as IIII for 4, but the modern standard form is what the converter returns.