Roman Numeral Converter

Convert Roman numerals

Turn numbers into Roman numerals and back, see how they're built, and write dates in numerals.

Free, private, no sign-up

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The seven symbols

Symbol	I	V	X	L	C	D	M
Value	1	5	10	50	100	500	1,000

Common values

Number	Numeral	Number	Numeral
1	I	6	VI
2	II	7	VII
3	III	8	VIII
4	IV	9	IX
5	V	10	X
50	L	100	C
500	D	1,000	M

How numerals are built

Write the thousands, then the hundreds, tens and units, largest first, and add them up. A smaller symbol before a larger one is taken away instead, but only in six pairs: IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900). So 1994 is M (1000) + CM (900) + XC (90) + IV (4) = MCMXCIV.

Good to know

Why does my clock show IIII instead of IV?

Many clock faces use IIII for 4, a tradition that balances the VIII opposite. The converter accepts IIII and tells you the standard form is IV.

Why is 3,999 the largest number?

Standard numerals repeat a symbol at most three times, and M (1,000) is the largest symbol, so MMMCMXCIX (3,999) is the largest you can write. Bigger numbers used a bar over a numeral to multiply it by 1,000, which isn't part of standard form.

Is there a Roman numeral for zero?

No. The Romans had no numeral for zero, and no negative numbers or fractions in this system.

How do I write a date in Roman numerals?

Choose Date, pick the day, and choose the order and separator. 31 October 2026 is XXXI.X.MMXXVI, day first, or X.XXXI.MMXXVI, month first. Check the order you want before a tattoo or an engraving.

What if I type something that isn't a standard numeral?

You'll get the standard spelling of what it was probably meant to be. For example, IC isn't standard, and 99 is written XCIX.