Math

Instant, private, and free

Roman Numeral Converter.

Convert between numbers and Roman numerals (I, V, X, L, C, D, M)

On-device calculationNo signup
01

Set your values

Results update as you type.

Roman Numeral Guide:

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

How to Use

Roman Numeral Conversion Rules

  • I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1000
  • When a smaller value appears before a larger value, subtract it (IV = 4)
  • When a smaller value appears after a larger value, add it (VI = 6)

FAQs

How do you convert numbers to Roman numerals?

Start with the largest Roman numeral values (M=1000, D=500, etc.) and subtract them from your number, adding the symbols as you go.

What is the largest number in Roman numerals?

Using standard notation, 3999 (MMMCMXCIX) is the largest. For larger numbers, a bar above the numeral multiplies it by 1000.