How do I read Roman numerals?

Roman numerals use letters: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Add values left to right: XVII = 10+5+1+1 = 17. Subtract when smaller precedes larger: IV = 5-1 = 4, IX = 10-1 = 9, XL = 50-10 = 40, CM = 1000-100 = 900.

What is the largest number in Roman numerals?

Standard Roman numerals max at 3,999 (MMMCMXCIX). Larger numbers use vinculum (overline) to multiply by 1,000: V̄ = 5,000, M̄ = 1,000,000. In practice, years (MMXXVI = 2026) and Super Bowl numbers are most common uses.

What are the rules for writing Roman numerals?

Rules: 1) Don't repeat I, X, C, M more than 3 times. 2) Never repeat V, L, D. 3) Subtract only I before V/X, X before L/C, C before D/M. 4) Write from largest to smallest (except subtractive). IIII is sometimes used on clock faces.

Where are Roman numerals still used today?

Roman numerals appear in: Super Bowl numbers (Super Bowl LVIII), movie sequels, copyright years in films, clock faces, book chapters, outline numbering, monarchs (King Charles III), and academic numbering.

How do I write years in Roman numerals?

2026 = MMXXVI (2000+20+6). Break down: M=1000, MM=2000, XX=20, VI=6. Year 1999 = MCMXCIX (1000+900+90+9). Year 2024 = MMXXIV. The year is often seen in movie credits and building cornerstones.

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Roman Numeral Converter

Roman numerals: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Add left to right: XVII = 17. Subtract when smaller precedes larger: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900. Maximum standard: 3999 (MMMCMXCIX).

Convert numbers to Roman numerals and Roman numerals to numbers. Supports values from 1 to 3999.

Enter Number (1-3999)

Roman Numeral Reference

I	1
V	5
X	10
L	50

C	100
D	500
M	1000

IV	4
IX	9
XL	40
XC	90

CD	400
CM	900

Roman Numeral Rules

Subtractive notation: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900
Maximum value: 3999 (MMMCMXCIX)
No symbol repeats more than 3 times consecutively
Used for: years, clock faces, outlines, Super Bowls

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Frequently Asked Questions

How do I read Roman numerals?: Roman numerals use letters: I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Add values left to right: XVII = 10+5+1+1 = 17. Subtract when smaller precedes larger: IV = 5-1 = 4, IX = 10-1 = 9, XL = 50-10 = 40, CM = 1000-100 = 900.
What is the largest number in Roman numerals?: Standard Roman numerals max at 3,999 (MMMCMXCIX). Larger numbers use vinculum (overline) to multiply by 1,000: V̄ = 5,000, M̄ = 1,000,000. In practice, years (MMXXVI = 2026) and Super Bowl numbers are most common uses.
What are the rules for writing Roman numerals?: Rules: 1) Don't repeat I, X, C, M more than 3 times. 2) Never repeat V, L, D. 3) Subtract only I before V/X, X before L/C, C before D/M. 4) Write from largest to smallest (except subtractive). IIII is sometimes used on clock faces.
Where are Roman numerals still used today?: Roman numerals appear in: Super Bowl numbers (Super Bowl LVIII), movie sequels, copyright years in films, clock faces, book chapters, outline numbering, monarchs (King Charles III), and academic numbering.
How do I write years in Roman numerals?: 2026 = MMXXVI (2000+20+6). Break down: M=1000, MM=2000, XX=20, VI=6. Year 1999 = MCMXCIX (1000+900+90+9). Year 2024 = MMXXIV. The year is often seen in movie credits and building cornerstones.