Convert numbers to Roman numerals and Roman numerals to numbers instantly. Works both ways, includes a date converter, year converter, step-by-step breakdown, and full reference chart. Updated .
Convert a full date to Roman numerals, popular for tattoos, wedding dates, anniversary inscriptions, and cornerstones. Each part (month, day, year) is converted separately.
Tap any row to convert it instantly.
| Roman | Value | Rule |
|---|---|---|
| IV | 4 | I before V = 5 − 1 = 4 |
| IX | 9 | I before X = 10 − 1 = 9 |
| XL | 40 | X before L = 50 − 10 = 40 |
| XC | 90 | X before C = 100 − 10 = 90 |
| CD | 400 | C before D = 500 − 100 = 400 |
| CM | 900 | C before M = 1000 − 100 = 900 |
Roman numerals aren't just a historical curiosity, they appear throughout modern life in ways most people take for granted. Clock and watch faces, movie and TV copyright dates (a film might show 'MMXXIV' for 2024 in the credits), Super Bowl numbering (Super Bowl LVIII = 58), Olympic Games, monarchs and popes (King Charles III, Pope Francis I), book preface pagination, and architectural cornerstones all use Roman numerals. The Roman numeral system uses seven symbols: I (1), V (5), X (10), L (50), C (100), D (500), and M (1,000). The subtractive notation rule is what trips people up: a smaller symbol placed before a larger one is subtracted rather than added. IV = 4 (not 6), IX = 9, XL = 40, XC = 90, CD = 400, CM = 900. All other combinations are additive: VI = 6, XI = 11, LX = 60, CX = 110, DC = 600. The largest number expressable in standard Roman numerals is 3,999 (MMMCMXCIX). Numbers above 3,999 require a bar over a numeral (vinculum) to indicate multiplication by 1,000, a convention rarely used outside of historical or academic contexts. This is one reason Roman numerals were ultimately replaced by the Hindu-Arabic numeral system for arithmetic, try performing long division in Roman numerals to appreciate why.
Roman numerals are a numeral system that originated in ancient Rome and used combinations of letters from the Latin alphabet to represent values. They remained the standard numeral system in Europe through the Middle Ages and are still widely used today for clock faces, book chapters, film sequels, Super Bowls, years on buildings, and tattoos.
| Symbol | Value | Origin | Example Use |
|---|---|---|---|
| I | 1 | One finger / tally mark | Chapter I, Super Bowl I |
| V | 5 | Open hand (5 fingers) | Five, clock faces |
| X | 10 | Two V's crossed / 10 fingers | Ten, Roman X |
| L | 50 | Half of C (100) | Fifty |
| C | 100 | Latin "centum" (hundred) | Century, cents |
| D | 500 | Half of Φ (1000) | Five hundred |
| M | 1000 | Latin "mille" (thousand) | Millennium, years |
When a smaller numeral appears before a larger one, you subtract rather than add. Only six subtractive combinations are used: IV (4), IX (9), XL (40), XC (90), CD (400), CM (900). Every other combination adds left to right. This rule is why 4 is IV and not IIII, though IIII still appears on some clock faces.
| Roman | Year | Notable Event |
|---|---|---|
| MCMXCIX | 1999 | Turn of the millennium |
| MM | 2000 | Year 2000 / Y2K |
| MMIV | 2004 | Athens Olympics |
| MMVIII | 2008 | Beijing Olympics, financial crisis |
| MMXII | 2012 | London Olympics |
| MMXVI | 2016 | Rio Olympics |
| MMXX | 2020 | Tokyo Olympics (delayed to 2021) |
| MMXXIV | 2024 | Paris Olympics |
| MMXXV | 2025 | Current year |
| MMXXVI | 2026 | FIFA World Cup, Milan Olympics |
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