Roman Numeral Converter
Convert numbers to Roman numerals and back. Free, no sign-up, works in your browser.
| I | V | X | L | C | D | M |
|---|---|---|---|---|---|---|
| 1 | 5 | 10 | 50 | 100 | 500 | 1000 |
🔒 100% private — processing happens in your browser. Nothing is uploaded.
How to use the Roman numeral converter
- Type a number from 1 to 3999 to see it in Roman numerals.
- Or type Roman numerals to get the number.
- Invalid numerals like IIII or VX are explained with the correct form.
Roman numerals appear on clocks, book chapters, film credits, Super Bowl names and tattoos of important dates. Subtractive pairs (IV, IX, XL, XC, CD, CM) keep them short. The converter checks the strict modern form, so the result is always correct for engraving or printing.