Nerd Tools
Large Roman Numeral Converter
Convert integers up to 3,999,999 to Roman numerals using vinculum notation — a bar (overline) above a numeral multiplies its value by 1,000. Supports conversion in both directions: decimal to Roman and Roman to decimal.
Standard I V X L C D M — no overline input needed for values under 4000
Vinculum Reference
| I | 1 | V̄ | 5,000 |
| V | 5 | X̄ | 10,000 |
| X | 10 | L̄ | 50,000 |
| L | 50 | C̄ | 100,000 |
| C | 100 | D̄ | 500,000 |
| D | 500 | M̄ | 1,000,000 |
| M | 1,000 |