Question 1

How do I convert a number to a Roman numeral?

Accepted Answer

Enter any integer from 1 to 3999 in the Number box. The Roman numeral form appears instantly. The converter uses the standard subtractive notation (e.g. 4 = IV, 9 = IX, 1994 = MCMXCIV).

Question 2

What is the largest number that can be written as a Roman numeral?

Accepted Answer

Standard Roman numerals support numbers from 1 to 3999 (M to MMMCMXCIX). For larger numbers, the overline or vinculum system is used in some historical contexts, but most modern uses stop at 3999.

Question 3

Are Roman numerals case-sensitive?

Accepted Answer

Roman numerals are written in uppercase by convention (I, V, X, L, C, D, M). Lowercase versions (i, v, x, etc.) work the same way and are accepted by this tool.

Question 4

What does subtractive notation mean?

Accepted Answer

Subtractive notation writes a smaller numeral before a larger one to subtract (IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900). The reverse order (additive) is invalid in standard Roman numerals.

I	1	XX	20	CCC	300
II	2	XXX	30	CD	400
III	3	XL	40	D	500
IV	4	L	50	DC	600
V	5	LX	60	DCC	700
VI	6	LXX	70	DCCC	800
VII	7	LXXX	80	CM	900
VIII	8	XC	90	M	1000
IX	9	C	100	MM	2000
X	10	CC	200	MMM	3000

📚 Roman Numeral Reference