Roman Numeral Converter
Convert between numbers and Roman numerals
Result
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Quick Examples
Roman Numeral Reference
Roman Numeral Rules
1. I, X, C, M can be repeated up to 3 times (III=3, XXX=30)
2. V, L, D cannot be repeated (VV is wrong, use X instead)
3. Subtraction rule: I before V/X (IV=4, IX=9), X before L/C (XL=40, XC=90), C before D/M (CD=400, CM=900)
4. Larger values are written first (left to right: thousands, hundreds, tens, ones)
5. Standard Roman numerals can represent 1 to 3,999
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Roman Numeral Translator
Convert Arabic numbers to Roman numerals and vice versa. Our converter handles numbers from 1 to 3,999 and validates Roman numeral input for correctness.
Basic Roman Numerals
- I = 1
- V = 5
- X = 10
- L = 50
- C = 100
- D = 500
- M = 1000
Common Examples
- IV = 4 (5-1)
- IX = 9 (10-1)
- XL = 40 (50-10)
- XC = 90 (100-10)
- CD = 400 (500-100)
- CM = 900 (1000-100)
- MCMXCIX = 1999
- MMXXIV = 2024
Uses of Roman Numerals Today
- Clock and watch faces
- Copyright dates (films, books)
- Outlines and lists (I, II, III)
- Monarchs and popes (Elizabeth II, Pope John Paul II)
- Super Bowl numbering
- Building cornerstones