Roman Numeral Converter
Free Online Roman ↔ Arabic Number Converter
Convert Arabic numerals to Roman numerals and vice versa. Supports range 1-3999 with validation.
🏛️ What are Roman Numerals?
Roman numerals originated in ancient Rome, using 7 symbols (I, V, X, L, C, D, M) to represent numbers. They are still used in clocks, movie credits, chapter numbering, and more.
📋 Base Symbols
I= 1
V= 5
X= 10
L= 50
C= 100
D= 500
M= 1,000
📜 Roman Numeral Rules
- Same symbol max 3 times in a row (III=3, XXX=30)
- Smaller before larger means subtract (IV=4, IX=9)
- Larger before smaller means add (VI=6, XI=11)
- V, L, D cannot be repeated
📊 Conversion Examples
| Arabic | Roman |
|---|---|
| 1 | I |
| 4 | IV |
| 9 | IX |
| 14 | XIV |
| 42 | XLII |
| 99 | XCIX |
| 399 | CCCXCIX |
| 500 | D |
| 944 | CMXLIV |
| 1,776 | MDCCLXXVI |
| 2,026 | MMXXVI |
| 3,999 | MMMCMXCIX |
📖 How to Use
- Choose conversion direction (Number→Roman or Roman→Number)
- Enter your value
- Click Convert to see the result
💡 Roman Numeral Tips
- Current year 2026 = MMXXVI
- Clocks often show 4 as IIII instead of IV
- There is no Roman numeral for zero
- Largest standard number: 3999 = MMMCMXCIX
- Used in Super Bowl, Olympics, and more