How to use the Roman Numeral Converter
- Type a number from 1 to 3999, or a Roman numeral such as XIV.
- Read the Roman numeral and the number.
- If your numeral is not standard, the converter shows the correct form.
- Use it to check dates, chapter numbers or clock faces.
Formula used
Symbols: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1000. A smaller symbol before a larger one is subtracted (IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900).
Worked example
Here is the Roman Numeral Converter worked through with the example values shown above, so you can check each step by hand.
| Inputs | |
|---|---|
| Number or Roman numeral | 2026 |
| Result | |
| Roman numeral | MMXXVI |
| Number | 2026 |
The seven symbols
I is 1, V is 5, X is 10, L is 50, C is 100, D is 500 and M is 1,000. Numbers are built by adding symbols from largest to smallest, so XVI is 10 + 5 + 1 = 16, and MMXXVI is 1000 + 1000 + 10 + 10 + 5 + 1 = 2026.
A symbol can be repeated up to three times in a row. Four in a row is written with subtraction instead.
Subtractive notation
When a smaller symbol comes before a larger one, it is subtracted: IV is 4, IX is 9, XL is 40, XC is 90, CD is 400 and CM is 900. Only I, X and C can be used this way, and only before the next two larger symbols. So 1994 is MCMXCIV: M (1000) + CM (900) + XC (90) + IV (4).
Reading it back, MCMXCIV gives 1994. The largest number the standard symbols can write is MMMCMXCIX, which is 3999.
Non-standard numerals
Some forms are read in practice but are not the standard form, such as IIII for 4 on many clock faces, or VIX for 4. The converter reads the value but flags that the standard form differs, so you can see the correct numeral.
There is no Roman numeral for zero, and there are no negative numbers or fractions in the standard system. Larger numbers were written with a bar over the symbol to multiply by 1,000, which this tool does not support.
Where you will see them
Roman numerals mark the Super Bowl, the Olympic Games editions, film sequels, copyright years in credits, outline headings and the names of monarchs and popes. Years are read as numbers: MMXXVI is 2026.
A quick check for a year: split it into thousands, hundreds, tens and ones and convert each part separately.
Tips for reading and writing Roman numerals
Work from the largest symbol down. To write 1,987, take 1000 (M), 900 (CM), 80 (LXXX) and 7 (VII), giving MCMLXXXVII. To read a numeral, scan left to right and subtract any symbol that is smaller than the one after it.
Common years are worth memorising: MM is 2000, MCM is 1900, and MMXX to MMXXX covers 2020 to 2030. Century marks on old buildings often use MDCCC style for 1800.
Frequently asked questions
What is the largest Roman numeral I can write?
3,999, written MMMCMXCIX, with the standard seven symbols.
Why is 4 sometimes written IIII?
It is a traditional form used on many clock faces. The standard form is IV.
Is there a Roman numeral for zero?
No. The Romans had no symbol for zero.
How do I read MCMXCIV?
M (1000) + CM (900) + XC (90) + IV (4) = 1994.
Can a symbol be repeated?
I, X, C and M can repeat up to three times in a row. V, L and D are not repeated.
Is the converter case sensitive?
No. You can type lower-case letters.
This calculator gives estimates for information only. Actual figures from a bank, employer, tax authority or doctor may differ. It is not financial, tax, legal or medical advice.