Roman Numeral Converter
Roman Numeral Symbols
How Roman Numbers Work
Roman Numerals read from left to right. Typically the largest number comes first, with smaller numbers following.
The following sequence reads 1 to 10 using addititive notation.
I, II, III, IIII, V, VI, VII, VIII, VIIII, X
While additive notation is used in some cases, Roman Numerals are commonly expressed using subtractive notation, where a person expresses 4 as 1 less than 5 [IV] instead of adding 1 four times [IIII]. The same expression is used for 9 as being 1 less than 10.
I, II, III, IV, V, VI, VII, VIII, IX, X
The pattern for expressing numbers by the power of 10 is the same.
X, XX, XXX, XL, L, LX, LXX, LXXX, XC, C
The pattern for expressing numbers by the power of 100 is also the same.
C, CC, CCC, CD, D, DC, DCC, DCCC, CM, M.
When a smaller number appears before a larger number it indicates subtractive notation applying to the symbol to the right.
874 = 800 + 70 + 4 = DCCC + LXX + IV = DCCCLXXIV.
If the number has a zero in it, that number is skipped.
409 = 400 + 9 = CD + IX = CDIX.
Writing Larger Numbers
- Some Romans would use a vinculum above a Roman number to indicate the number is multiplied by 1,000.
- Large numbers of 100,000 or more are expressed with a frame around them that is open at the bottom. This frame would indicate the portion of the number inside the frame be multiplied by 100,000.