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Roman Numeral Converter

Type a number or a Roman numeral and get the conversion instantly, with each step explained.

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How to use Roman Numeral Converter

  1. 1Type a number between 1 and 3999, such as 2026, or a Roman numeral such as MCMXCIV.
  2. 2The tool detects which one you entered and converts it immediately.
  3. 3Check the breakdown to see which symbols add up to the result.
  4. 4Click Copy to use the result, or try one of the examples.

Convert to and from Roman numerals

Roman numerals still appear in many places: years on films and buildings, clock faces, book chapters, monarchs and popes, sporting events, outlines and tattoos. This converter works in both directions — type an ordinary number to get its Roman numeral, or type a Roman numeral to get the number. It shows how the result is built from individual symbols, so it's also a handy way to learn the system or check homework.

Features

  • Automatic detection: enter digits or letters, and the tool picks the right direction.
  • Full standard range from 1 (I) to 3999 (MMMCMXCIX).
  • Step-by-step breakdown of every symbol and its value.
  • Strict validation that catches non-standard numerals such as IIII or VX.
  • Quick examples and a reference table of all seven symbols.

The seven symbols

Symbol I V X L C D M
Value 1 5 10 50 100 500 1000

The rules

  1. Add symbols from largest to smallest. VIII = 5 + 1 + 1 + 1 = 8.
  2. Subtract when a smaller symbol comes first. Only six pairs are used: IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900).
  3. Repeat a symbol at most three times. 3 is III, but 4 is IV rather than IIII.
  4. Never repeat V, L or D. 10 is X, not VV.

Useful conversions

Number Roman numeral
1–10 I, II, III, IV, V, VI, VII, VIII, IX, X
50 L
100 C
500 D
1000 M
1999 MCMXCIX
2000 MM
2025 MMXXV
2026 MMXXVI

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Frequently asked questions

How do Roman numerals work?
Seven letters stand for values: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500 and M = 1000. Symbols are written from largest to smallest and added together, so XVI = 10 + 5 + 1 = 16. When a smaller symbol comes before a larger one, it is subtracted: IV = 4, IX = 9, XL = 40, XC = 90, CD = 400 and CM = 900.
How do you write 2026 in Roman numerals?
2026 is MMXXVI — MM for 2000, XX for 20 and VI for 6.
Why is the maximum 3999?
In standard notation a symbol can be repeated at most three times, and M (1000) is the largest letter, so MMMCMXCIX (3999) is the largest number that can be written. Larger numbers historically used a bar over a letter to multiply it by 1000, which isn't part of the standard form.
Is there a Roman numeral for zero?
No. The Roman system had no symbol for zero; the concept was described with the Latin word nulla. Negative numbers and fractions in decimal form can't be written either.
Why is IIII not accepted?
The converter only accepts the standard subtractive form, so 4 is IV and 9 is IX. IIII does appear on some clock faces for visual balance, but it isn't the standard way to write the number.
How do I write a date in Roman numerals?
Convert the day, the month and the year separately and join them with dots or dashes. For example, 14 July 2026 becomes XIV.VII.MMXXVI. Popular for tattoos and wedding dates — double-check each part before making anything permanent.

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