Roman Numeral Converter
Convert numbers to Roman numerals and Roman numerals to numbers from 1 to 3999, with a step-by-step breakdown and validation.
Convert a whole number from 1 to 3999 into a Roman numeral.
Whole numbers from 1 to 3999. Results update as you type.
Roman Numeral
Value: 2026
How was 2026 converted?
Break the number into place values, and write each one in Roman numerals:
- 2000 → MM
- 20 → XX
- 6 → VI
2026 = MM + XX + VI
2000 + 20 + 6 = 2026
Therefore: 2026 = MMXXVI
Verify the conversion
Reading MMXXVI back gives 2026, the number you entered.
Need to work with the value after converting? Use the Scientific Calculator, or check whether it is prime with the Prime Number Calculator.
Roman numeral symbols
| I | V | X | L | C | D | M |
|---|---|---|---|---|---|---|
| 1 | 5 | 10 | 50 | 100 | 500 | 1000 |
This Roman numeral converter works in both directions: turn a number from 1 to 3999 into Roman numerals, or enter a Roman numeral (upper or lower case) to get its value. Every result shows how it was converted, place value by place value, and Roman numeral input is checked against standard notation, so a non-standard form such as IIII or IL is flagged with the reason instead of being turned into a wrong number.
Worked Calculation Examples
| Scenario | Result | Calculation Step |
|---|---|---|
| 2026 to Roman numerals | MMXXVI | 2026 = 2000 + 20 + 6. 2000 → MM, 20 → XX, 6 → VI, so 2026 = MMXXVI. |
| 49 to Roman numerals (subtractive notation) | XLIX | 49 = 40 + 9. 40 → XL (10 before 50, so 50 − 10) and 9 → IX (1 before 10, so 10 − 1). Writing IL is not standard. |
| 1994 to Roman numerals (several subtractive pairs) | MCMXCIV | 1994 = 1000 + 900 + 90 + 4 = M + CM + XC + IV = MCMXCIV. |
| MMXXIV to a number | 2024 | MM = 2000, XX = 20, IV = 4. 2000 + 20 + 4 = 2024. |
| 8 to Roman numerals | VIII | 8 = 5 + 1 + 1 + 1, so it is written additively as VIII. I can repeat up to three times after V. |
How Roman Numerals Work
Roman numerals use seven symbols: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, and M = 1000.
Additive notation: when a symbol is followed by symbols of equal or smaller value, the values are added. VI = 5 + 1 = 6, XV = 10 + 5 = 15, and XXVI = 10 + 10 + 5 + 1 = 26.
Subtractive notation: six pairs place a smaller symbol before a larger one to subtract it. IV = 5 − 1 = 4, IX = 10 − 1 = 9, XL = 50 − 10 = 40, XC = 100 − 10 = 90, CD = 500 − 100 = 400, and CM = 1000 − 100 = 900.
What Makes a Roman Numeral Standard
Standard modern notation writes each place value once, from thousands down to ones, and follows a few rules. Only I, X, and C are used subtractively, and only before the next two larger symbols: I before V or X, X before L or C, C before D or M. V, L, and D are never repeated and never subtracted. I, X, C, and M repeat at most three times in a row.
So 4 is IV rather than IIII, 49 is XLIX rather than IL, and 99 is XCIX rather than IC. Every number from 1 to 3999 has exactly one standard form, which is what this converter produces and accepts.
Why the Converter Stops at 3999
The largest value standard notation can write is 3999, MMMCMXCIX, because M may repeat only three times. Extended notation handles larger values, for example by drawing a line over a symbol to multiply it by 1,000, but conventions vary, so this converter intentionally keeps to the standard 1 to 3999 range. Roman numerals also have no symbol for zero.
Where Roman Numerals Are Used Today
You will still see Roman numerals on some clock faces, in book chapter and volume numbers, in film sequel titles and the copyright years in film credits, in the names of monarchs and popes (Elizabeth II), in numbered events and editions such as the Super Bowl, and in formal outlines and document sections. Converting a year is one of the most common uses: 2026 is MMXXVI.
The system itself dates from ancient Rome. Hindu-Arabic digits, with place value and a zero, gradually replaced it for everyday arithmetic in Europe from around the 13th century.
How to Use the Roman Numeral Converter
- Choose Number → Roman or Roman → Number.
- Enter a whole number from 1 to 3999, or a Roman numeral such as MMXXIV (upper or lower case). The result updates as you type.
- Read the converted result, and use Copy to copy it.
- Follow the breakdown to see how each place value (thousands, hundreds, tens, ones) was converted.
- For Roman numeral input, read the validation note: it confirms the notation is standard, or explains exactly what is wrong.
- Try one of the examples, or Reset, to compare another conversion.
Frequently Asked Questions
What are Roman numerals?
Roman numerals are a number system that uses seven letters as symbols: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, and M = 1000. Numbers are formed by combining them, for example XXVI = 26.
How do I convert a number to Roman numerals?
Split the number into thousands, hundreds, tens, and ones, then write each part with the largest symbols first. For 1994: 1000 → M, 900 → CM, 90 → XC, 4 → IV, so 1994 = MCMXCIV.
How do I convert Roman numerals to numbers?
Read from left to right and add the values. When a smaller symbol comes directly before a larger one in a valid subtractive pair (IV, IX, XL, XC, CD, CM), subtract it instead. MMXXIV = 1000 + 1000 + 10 + 10 + (5 − 1) = 2024.
What does IV mean?
IV means 4. I appears before V, so 1 is subtracted from 5.
What does IX mean?
IX means 9. I appears before X, so 1 is subtracted from 10.
What is XL in Roman numerals?
XL is 40. X appears before L, so 10 is subtracted from 50.
What is XC in Roman numerals?
XC is 90. X appears before C, so 10 is subtracted from 100.
What is CD in Roman numerals?
CD is 400. C appears before D, so 100 is subtracted from 500.
What is CM in Roman numerals?
CM is 900. C appears before M, so 100 is subtracted from 1000.
Can Roman numerals represent zero?
No. Standard Roman numeral notation has no symbol for zero, so this converter accepts numbers from 1 upward.
Can Roman numerals represent numbers above 3999?
Not in standard notation, where M repeats at most three times, so the largest value is 3999 (MMMCMXCIX). Extended notations, such as an overline that multiplies a symbol by 1,000, can write larger numbers, but this converter uses the standard 1 to 3999 range.
Is IL a valid Roman numeral?
No. I can only be subtracted from V and X, so IL is not a standard way to write 49. The standard form is XLIX: XL (40) + IX (9).
Is IIII valid?
IIII is not the standard modern way to write 4, because I repeats at most three times in a row. The standard form is IV. IIII does still appear on some clock faces as a traditional style.
Can I convert years into Roman numerals?
Yes, any year from 1 to 3999. For example, 1776 is MDCCLXXVI, 2024 is MMXXIV, and 2026 is MMXXVI.
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Last updated: September 27, 2026.