Roman Numeral Converter

Convert numbers to Roman numerals and back (1–3999), e.g. 2026 = MMXXVI – with the breakdown into symbols and a check for non-standard forms.

Runs locally in your browser
Roman numeralMMXXVI
Breakdown
M1000M1000X10X10V5I1=2026
The symbols
I1V5X10L50C100D500M1000

Smaller symbols in front of larger ones are subtracted (IV = 4, XC = 90), otherwise they are added (VI = 6). The same symbol appears at most three times in a row.

About this tool

Roman numerals show up on clock faces, in chapter numbers, with kings and popes, in film credits and as years on buildings or tattoos. This tool converts in both directions: enter a number like 2026 and you get MMXXVI, enter MCMXCIV and you get 1994. It recognises what you typed by itself.

For every result you see the breakdown into its symbols, e.g. M + CM + XC + IV. Spellings like IIII (on some clocks) or IC are read too, with a hint to the standard form. For other number systems use the Number Base & Roman Numeral Converter; to write numbers in words, use Number to Words.

How it works

  1. Enter a whole number from 1 to 3999 or a Roman numeral – upper or lower case does not matter.
  2. Read the result and copy it with one click.
  3. Under “Breakdown” you see which symbols the number is made of.

Frequently asked questions

How do Roman numerals work?

There are seven symbols: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1000. They are added from large to small (VIII = 8). A smaller symbol in front of a larger one is subtracted: IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900.

Why does it stop at 3999?

With seven symbols and the rule “at most three in a row”, MMMCMXCIX = 3999 is the largest number. Larger values were written with a bar over the symbol (times 1000); that notation was never consistent, so the tool does not support it. The Romans had no zero.

Is IIII wrong?

The standard spelling of 4 is IV. Many clocks still show IIII, and the additive form also appears in old inscriptions. The tool reads such forms but shows the standard spelling.

How do I write a date in Roman numerals?

Convert day, month and year separately and separate them with dots, e.g. 29.10.2026 = XXIX.X.MMXXVI. “This year” fills in the current year directly.

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