Roman Numeral Converter
Guide: Roman Numerals and Writing Numbers in Words
2024 in Roman numeralsMMXXIV
The seven letters
- I
- 1
- V
- 5
- X
- 10
- L
- 50
- C
- 100
- D
- 500
- M
- 1000
Smaller letters before larger ones are subtracted (IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900). Otherwise letters are added, and the same letter is used at most three times in a row.
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How to use
- 1Type a number from 1 to 3999, or a Roman numeral.
- 2The conversion appears straight away.
- 3Check the reference for the seven letters and the subtraction rule.
- 4Click Copy to copy the result.
Frequently asked questions
How do Roman numerals work?
Seven letters stand for values: I is 1, V is 5, X is 10, L is 50, C is 100, D is 500 and M is 1000. Letters are added, except that a smaller letter before a larger one is subtracted, so IV is 4 and IX is 9.
What is the largest number?
The standard form goes up to 3999 (MMMCMXCIX). Larger numbers need a bar over the letters to multiply by 1000, which isn't supported here.
Why is IIII or IC not accepted?
The standard rules allow a letter at most three times in a row, and only I, X and C can be subtracted from the next two larger values. So 4 is IV and 99 is XCIX. Clocks sometimes use IIII, but it isn't standard.
Is there a Roman numeral for zero?
No. The Romans had no symbol for zero, so the converter starts at 1.
Read the guide
Learn how this works and how to get the most from it.
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Roman Numerals and Writing Numbers in Words
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