Roman Numerals Conversion
REFRoman Numeral Symbols
| Symbol | Value | Symbol | Value |
|---|---|---|---|
| I | 1 | C | 100 |
| V | 5 | D | 500 |
| X | 10 | M | 1,000 |
| L | 50 |
Roman Numerals 1-100
| Arabic | Roman | Arabic | Roman | Arabic | Roman | Arabic | Roman |
|---|
Key Numbers
| Arabic | Roman | Arabic | Roman |
|---|---|---|---|
| 50 | L | 500 | D |
| 100 | C | 1,000 | M |
| 200 | CC | 2,000 | MM |
| 300 | CCC | 3,000 | MMM |
| 400 | CD | 4,000 | MV̅ |
| 500 | D | 5,000 | V̅ |
| 600 | DC | 10,000 | X̅ |
| 700 | DCC | 50,000 | L̅ |
| 800 | DCCC | 100,000 | C̅ |
| 900 | CM | 1,000,000 | M̅ |
Roman Numeral Rules
Additive Principle
When symbols are arranged from largest to smallest, add their values. Example: VII = 5+1+1 = 7
Subtractive Principle
A smaller symbol before a larger one means subtract. Example: IV = 5-1 = 4, IX = 10-1 = 9
Repetition Rule
Symbols can repeat up to 3 times. Example: III = 3, XXX = 30, CCC = 300
No Repetition
V, L, D cannot be repeated. Use IV (not IIII), XL (not XXXX), CD (not CCCC)
Subtraction Restrictions
Only I, X, C can be subtracted. I before V or X, X before L or C, C before D or M
Using Roman Numerals
Roman numerals use letters to represent numbers: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Symbols are combined using additive and subtractive principles. Reading left to right, if a symbol is followed by a larger one, subtract (IV=4). Otherwise add (VI=6). Still used today for clock faces, book chapters, movie sequels, Super Bowl numbers, and formal documents.