About the Roman Numeral Converter
Convert numbers to Roman numerals (2026 → MMXXVI) and back. Enter one value per line; the direction is detected automatically and invalid numerals are flagged.
Key features
- Numbers to Roman numerals and back
- Automatic direction for each line
- Strict validation: rejects IIII, VX and IC
- Converts many values at once, one per line
- Uppercase or lowercase input
- Covers the standard range 1 to 3,999
Convert between numbers and Roman numerals
Roman numerals still appear on clock faces, in book chapters, movie sequels, Super Bowl names, monarchs' names, outlines and tattoos. Enter numbers or numerals, one per line, and each is converted in the right direction automatically.
The seven symbols
| Symbol | I | V | X | L | C | D | M |
|---|---|---|---|---|---|---|---|
| Value | 1 | 5 | 10 | 50 | 100 | 500 | 1,000 |
Rules
- Add symbols from largest to smallest: VI = 5 + 1 = 6.
- Subtract when a smaller symbol comes before a larger one, but only in these pairs: IV (4), IX (9), XL (40), XC (90), CD (400), CM (900).
- Repeat I, X, C and M at most three times in a row. V, L and D are never repeated.
Reference table
| Number | Roman | Number | Roman |
|---|---|---|---|
| 1 | I | 40 | XL |
| 4 | IV | 50 | L |
| 5 | V | 90 | XC |
| 9 | IX | 100 | C |
| 10 | X | 400 | CD |
| 14 | XIV | 500 | D |
| 19 | XIX | 900 | CM |
| 20 | XX | 1,000 | M |
Years
| Year | Roman |
|---|---|
| 1999 | MCMXCIX |
| 2000 | MM |
| 2024 | MMXXIV |
| 2025 | MMXXV |
| 2026 | MMXXVI |
Related tools
Spell numbers in English with Number to Words, or do math with the Scientific Calculator.
How to use the Roman Numeral Converter
- Type or paste your text into the input box.
- Choose the options you want.
- The result updates instantly as you type.
- Copy the output or download it as a .txt file.