Roman Numeral Converter

Convert between Roman numerals and standard numbers

About the Calculator

Roman numerals show up on clocks, book chapters, movie titles, and formal dates, and they can be easy to misread. This converter gives you a quick, reliable translation in either direction so you do not have to guess. Use it when you are writing a date, checking a year on a monument, or formatting a title with the right notation. It also helps students learn the rules behind subtractive pairs like IV and IX. If you want accurate results without memorizing the full system, this tool gives you the answer and reinforces the pattern at the same time. Use the Roman Numeral Converter to get a clear result you can act on right away.

Enter Number (1-3,999)

Roman Numeral

MMXXVI

Quick Reference

100

500

1000

The Formula

I=1, V=5, X=10, L=50, C=100, D=500, M=1000

Examples

MMXXVI

2026 (current year)

King Louis XIV

Prince partied like it was MCMXCIX

1999

CDXLIV

444

DCCCLXXXVIII

888

MMMDCCCLXXXVIII

3888

XLII

42 (the answer to everything).

LXVII

67... six seven...

💡 Tips

•Roman numerals use subtractive notation (IV = 4, IX = 9)
•Standard Roman numerals only go up to 3,999 (MMMCMXCIX)
•No symbol for zero exists in Roman numerals
•Commonly used for dates, outlines, and clock faces

🎉 Fun Facts

•The limit of 3,999 exists because there's no standard symbol for 5,000. The largest symbol M (1,000) can only be repeated 3 times by convention, giving MMM (3,000). Adding CMXCIX (999) gives the maximum: 3,999.
•Ancient Romans did write larger numbers using a vinculum (overline) to multiply by 1,000 — so V̅ meant 5,000 and X̅ meant 10,000 — but this notation isn't commonly used today.
•The Romans had no concept of zero, which is why there's no Roman numeral for it. The word 'nulla' (meaning 'none') was sometimes used in medieval times.