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Roman Numeral Converter

Convert a number from 1 to 3,999 into Roman numerals, or type a Roman numeral to get the number — the converter works out which way you are going. It also shows how the numeral is built from its parts.

Quick examples

A whole number from 1 to 3,999, or a numeral such as XLII.

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ConvertedMMXXVI
Conversion
Number → Roman numeral
How it breaks down
M (1000) + M (1000) + X (10) + X (10) + V (5) + I (1)

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      Formula

      I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1,000
      Symbols written from largest to smallest are added: VIII = 5 + 1 + 1 + 1 = 8
      A smaller symbol before a larger one is subtracted: IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900

      How to use it

      1. Type a whole number from 1 to 3,999, or a Roman numeral such as XLII.
      2. Read the conversion.
      3. The breakdown line shows each symbol group and its value.

      Worked examples

      2026 in Roman numerals

      Converted
      MMXXVI
      How it breaks down
      M (1000) + M (1000) + X (10) + X (10) + V (5) + I (1)

      1994 in Roman numerals

      Converted
      MCMXCIV
      How it breaks down
      M (1000) + CM (900) + XC (90) + IV (4)

      XLIX as a number

      Converted
      49
      Conversion
      Roman numeral → number

      The rules of standard Roman numerals

      A symbol is repeated at most three times in a row, so 4 is IV rather than IIII (although many clock faces do use IIII). V, L and D are never repeated.

      Only I, X and C are used for subtraction, and each only before the next two larger symbols: I before V or X, X before L or C, C before D or M. That is why 99 is XCIX and not IC. Numerals that break these rules are rejected.

      Limits

      The largest number in standard notation is 3,999 (MMMCMXCIX). Larger values historically used a bar over a numeral to multiply it by 1,000, which has no plain-text form. There is no Roman numeral for zero.

      Recent years: 2024 is MMXXIV, 2025 is MMXXV and 2026 is MMXXVI. The year 1999 is MCMXCIX.

      Questions people ask

      What is 2026 in Roman numerals?

      MMXXVI: M + M + X + X + V + I = 1,000 + 1,000 + 10 + 10 + 5 + 1.

      What number is XLIX?

      49. XL is 40 and IX is 9.

      Why is 4 written IV and not IIII?

      Standard notation allows a symbol only three times in a row, so 4 is written as “one before five”. IIII is an older form that survives on clock and watch dials.

      What is the largest Roman numeral?

      In standard notation, MMMCMXCIX, which is 3,999.

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