| Number | Roman Numeral |
|---|---|
| 1 | I |
| 2 | II |
| 3 | III |
| 4 | IV |
| 5 | V |
| 6 | VI |
| 7 | VII |
| 8 | VIII |
| 9 | IX |
| 10 | X |
| 11 | XI |
| 14 | XIV |
| 15 | XV |
| 19 | XIX |
| 20 | XX |
| 40 | XL |
| 50 | L |
| 90 | XC |
| 100 | C |
| 400 | CD |
| 500 | D |
| 900 | CM |
| 1000 | M |
| 1999 | MCMXCIX |
About Roman Numerals
Roman numerals are a number system that originated in ancient Rome and were widely used in Europe until the end of the Middle Ages. The numbers we use today like 1, 2, 3 are known worldwide as the **Hindu-Arabic number system** and are a more modern invention. Roman numerals still appear in clocks, book chapter numbering, movie production dates, and historical events (for example, World War II).
Basic Symbols
This system is based on different combinations of seven basic letters:
- I = 1
- V = 5
- X = 10
- L = 50
- C = 100
- D = 500
- M = 1000
Writing Rules
When writing Roman numerals, generally an order from larger value letters to smaller value letters is followed and the values are added (for example, VI = 5 + 1 = 6; CLXI = 100 + 50 + 10 + 1 = 161). However, there is also a "subtraction method" where a smaller value is written to the left of a larger value. In this case, the smaller value is subtracted from the larger value.
- IV = 4 (5 - 1)
- IX = 9 (10 - 1)
- XL = 40 (50 - 10)
- XC = 90 (100 - 10)
- CD = 400 (500 - 100)
- CM = 900 (1000 - 100)
Usage Areas
Roman numerals are still used in various areas today:
- Clocks and Watches: Traditional timepieces often use Roman numerals
- Book Chapters: Prefaces and chapter numbering
- Movie Credits: Copyright years in film production
- Historical Events: Wars, dynasties, and centuries
- Architecture: Building dates and inscriptions
- Formal Documents: Legal and official numbering
Conversion Rules
This converter allows you to correctly convert all numbers between 1 and 3999 according to these rules. The system works efficiently for smaller numbers but becomes cumbersome for very large numbers, which is why the Hindu-Arabic system became more popular for mathematical calculations.
Important Notes:
- The same symbol should not be repeated more than three times consecutively
- Only I, X, and C can be used for subtraction
- A smaller numeral can only be subtracted from the two next higher numerals
- V, L, and D cannot be repeated or used for subtraction