Calculators & Converters
Roman numeral converter
Type a number to see it in Roman numerals, or type a Roman numeral to see its value. Invalid numerals are caught with a clear message.
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- Runs in your browser
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Result
Table
How to use this tool
- Choose "Number to Roman" or "Roman to number".
- Type a whole number between 1 and 3999, or a Roman numeral such as MCMXCIV.
- Read the result straight away. An error message tells you if the numeral is not valid.
- Copy the result. The lowercase form is shown for numbers, handy for list numbering.
How it works
Roman numerals combine seven letters: I (1), V (5), X (10), L (50), C (100), D (500) and M (1000). Letters are written from largest to smallest and added together. When a smaller letter comes before a larger one it is subtracted, which gives IV for 4, IX for 9, XL for 40, XC for 90, CD for 400 and CM for 900.
2026 = MM (2000) + XX (20) + VI (6) = MMXXVI
1994 = M + CM + XC + IV = MCMXCIV
Good to know
The standard system has no zero and no symbol above 3999, because M cannot be repeated more than three times. Strict rules also limit repeats: I, X, C and M can repeat up to three times, and V, L and D never repeat. So IIII for 4 and VX for 5 are rejected. Some clock faces use IIII, which is a traditional exception, but the converter treats IV as the correct form.
Roman numerals are still used for book chapters, movie sequels, film copyright years, clock faces, monarch names and Super Bowl editions. Use lowercase numerals (i, ii, iii) for page numbers in a book's front matter.
Frequently asked questions
How do I write 2026 in Roman numerals?
MMXXVI: MM for 2000, XX for 20 and VI for 6.
What is the largest Roman numeral?
In the standard system it is MMMCMXCIX, which is 3999.
Why is IIII not accepted?
The standard rule writes 4 as IV. IIII appears on some clocks, but it is not the modern standard form.
Is there a Roman numeral for zero?
No. The Romans had no symbol for zero.