What are the basic Roman numeral symbols?

I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Combinations like IV=4, IX=9, XL=40, XC=90, CD=400, CM=900 use subtraction notation.

Why are Roman numerals still used today?

Roman numerals appear in clock faces, book chapters, movie sequel numbering, Super Bowl titles, building cornerstones, and formal document outlines. They convey a sense of permanence and tradition.

What is the largest Roman numeral?

Using standard notation (I through M), the largest representable number is 3999 (MMMCMXCIX). Numbers larger than 3999 historically used a bar over a numeral to multiply by 1000, but this isn't standard today.

Why is 4 written as IV and not IIII?

Subtractive notation — placing a smaller numeral before a larger one means subtraction. IV = 5 − 1 = 4. This rule applies to: I before V or X, X before L or C, and C before D or M.

Conversion

● Conversion

Roman numeral converter

Convert numbers to Roman numerals and back. Works for any value from 1 to 3999.

Arabic number (1–3999)

Roman numeral

MMXXIV

Reference

I=1V=5X=10L=50C=100D=500M=1000IV=4IX=9XL=40XC=90CD=400CM=900

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