Roman Numeral Converter
Type a number to see it in Roman numerals, or type Roman numerals to see the number. Dates are converted too.
The seven Roman numerals
I = 1
V = 5
X = 10
L = 50
C = 100
D = 500
M = 1000
The rules
- Symbols are added from largest to smallest: VIII = 5 + 3 = 8, and MDCLXVI = 1666.
- A smaller symbol before a larger one is subtracted, but only in six pairs: IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900). So 99 is XCIX, not IC.
- I, X, C and M can repeat up to three times. V, L and D never repeat. So 4 is IV, not IIII.
- Standard Roman numerals go up to 3999 (MMMCMXCIX). There is no zero.
When you type a numeral that breaks these rules (such as IIII or IC), the converter tells you and suggests the correct form. Clock faces often show IIII instead of IV, a tradition rather than a rule.
Common uses
Years on buildings, films and clocks (2026 = MMXXVI), book chapters and appendices, outlines (I, II, III), monarchs and popes (Elizabeth II), Super Bowl numbers, and tattoos of dates, for example 14 August 1947 written as XIV · VIII · MCMXLVII.
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How it works
- Enter — type or paste your values or text.
- Get the result — it is worked out in your browser.
- Adjust — change the inputs to compare, or copy the result.
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