Roman numerals
Convert numbers 1–3999 and standard subtractive Roman numerals in either direction.
Your inputs
Choose your dates and the calculation convention. Results update as you edit.
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Your result
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How it works
- I = 1; V = 5; X = 10; L = 50; C = 100; D = 500; M = 1000
- IV = 4; IX = 9; XL = 40; XC = 90; CD = 400; CM = 900
Assumptions and limitations
Use standard subtractive Roman numerals for 1–3999, such as IV, IX, or MMXXVI.
Sources
- Unicode — Number forms, Roman numeral symbols Sources reviewed: 2026-10-05
