Roman Numeral Converter
Both directions, 1 to 3999, with the subtractive pairs handled correctly rather than as naive symbol repetition.
Result
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Breakdown
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Worked example
2026 decomposes as 1000 + 1000 + 10 + 10 + 5 + 1, giving MMXXVI. The subtractive pairs — IV, IX, XL, XC, CD, CM — exist because the Romans preferred fewer symbols over strict addition.
Roman numerals are additive with a subtractive exception: a smaller symbol before a larger one is subtracted. That single rule is why 4 is IV rather than IIII, and why a naive symbol-repetition converter gets roughly a third of numbers wrong.
The range
Standard form covers 1 to 3999. Beyond that the Romans used overbars or other conventions that have no single modern encoding, so this converter refuses rather than inventing one.