⇄
Roman numeral reference
I1
V5
X10
L50
C100
D500
M1000
V̄5000
X̄10000
How Roman numerals work
- The seven base letters:
I=1, V=5, X=10, L=50, C=100, D=500, M=1000 - Additive rule: place larger then smaller (VI = 6, MCC = 1200)
- Subtractive rule: place smaller before larger to subtract (IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900)
- The same letter cannot appear more than 3 times in a row (so 4 is IV, not IIII)
- For numbers above 3,999 a bar (vinculum) over a letter multiplies it by 1000 — this tool uses V̄, X̄, L̄, C̄, D̄, M̄
Common use cases
- Movie credits and copyright years (©MMXXIV)
- Book chapters and outlines
- Clock faces and watch designs
- School assignments and history homework