Roman Numerals

Q: Why is 4 written IV and not IIII?

Standard notation uses the subtractive rule: IV (5 − 1). You will see IIII on some clock faces, but it is not the canonical form.

Q: What is the largest Roman numeral?

With the seven basic letters you can go up to 3999, written MMMCMXCIX. For bigger values the Romans drew a bar over a letter (the vinculum), multiplying it by a thousand — V means 5,000 (5 × 1,000). Since that notation is hard to type, this converter covers 1 to 3999.

By Bruno Tonetto · Reviewed on July 16, 2026 · How we verify

Roman numerals use seven letters to write numbers: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500 and M = 1000. Use the converter below to turn a whole number into Roman numerals (or back), check the reference chart, and practice with the quiz.

How Roman numerals work

Each letter has a fixed value. To write a number, the symbols add up from left to right — except when a smaller symbol appears before a bigger one, which means subtraction (the subtractive rule).

A smaller symbol after a bigger one adds: VI = 6 (5 + 1).
A smaller symbol before a bigger one subtracts: IV = 4 (5 − 1).
Handle ones, tens, hundreds and thousands separately: 99 is XCIX (90 + 9), not IC; 999 is CMXCIX, not IM.
I, X, C and M can repeat up to three times (III = 3); V, L and D never repeat.
There is no zero and there are no negative numbers in the Roman system.

Roman numerals chart

The seven symbols, with examples of each in use:

Value	Symbol	Examples
1	I	II = 2, III = 3, VIII = 8
5	V	IV = 4, VI = 6, VII = 7
10	X	IX = 9, XIV = 14, XXIV = 24
50	L	XL = 40, XLIX = 49, LXIX = 69
100	C	XC = 90, CIV = 104, CCLXIV = 264
500	D	CD = 400, CDXCI = 491, DXLIX = 549
1000	M	CM = 900, MXIV = 1014, MCDV = 1405

1 to 20

1	I
2	II
3	III
4	IV
5	V
6	VI
7	VII
8	VIII
9	IX
10	X
11	XI
12	XII
13	XIII
14	XIV
15	XV
16	XVI
17	XVII
18	XVIII
19	XIX
20	XX

Tens, hundreds and thousands

10	X
20	XX
30	XXX
40	XL
50	L
60	LX
70	LXX
80	LXXX
90	XC
100	C
200	CC
300	CCC
400	CD
500	D
600	DC
700	DCC
800	DCCC
900	CM
1000	M
2000	MM
3000	MMM

Examples: years and dates

Roman numerals show up all the time in dates, centuries and sequels — in movie credits (MCMXCIV = 1994), on clock faces and monuments, after the names of popes and monarchs (Henry VIII, Elizabeth II), and famously in the Super Bowl: Super Bowl LX (2026) is number 60. Here are some landmark years:

Year	In Roman numerals	Event
1492	MCDXCII	Columbus reaches the Americas
1620	MDCXX	the Mayflower lands at Plymouth
1776	MDCCLXXVI	Declaration of Independence
1787	MDCCLXXXVII	U.S. Constitution signed
1865	MDCCCLXV	end of the Civil War
1929	MCMXXIX	Wall Street crash
1969	MCMLXIX	Apollo 11 Moon landing
2000	MM	turn of the millennium
2026	MMXXVI	current year

Frequently asked questions

Why is 4 written IV and not IIII?

Standard notation uses the subtractive rule: IV (5 − 1). You will see IIII on some clock faces, but it is not the canonical form.

What is the largest Roman numeral?

With the seven basic letters you can go up to 3999, written MMMCMXCIX. For bigger values the Romans drew a bar over a letter (the vinculum), multiplying it by a thousand — V means 5,000 (5 × 1,000). Since that notation is hard to type, this converter covers 1 to 3999.

How do I read a long Roman numeral?

Add the values from left to right, remembering to subtract when a smaller symbol comes before a bigger one. In MCMXLIX: M (1000) + CM (900) + XL (40) + IX (9) = 1949. Or just type it into the converter.

Is there a zero in Roman numerals?

No. The Roman system has no symbol for zero — the concept itself wasn't part of Roman arithmetic, one reason calculations were laborious and the Hindu–Arabic system (0 through 9) eventually won out.

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The converter covers the standard Roman system, from 1 to 3,999.

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