How to use the Roman Numeral Converter tool
- Type a number or numeralEnter a number like 2026 or Roman numerals like MCMXCIV. The tool detects which one you typed.
- Read the resultThe conversion appears instantly, with a breakdown of each symbol and its value.
- Check the spellingNon-standard numerals such as IIII are flagged, with the standard form shown.
- Convert a dateOpen “Convert a date” for birthdays, anniversaries and tattoo dates in Roman numerals.
Features
- Automatic directionNumbers become numerals and numerals become numbers, with no buttons to press.
- Step-by-step breakdownSee how a number is built, e.g. 1994 = M + CM + XC + IV.
- ValidationSpots invalid letters and non-standard forms, and suggests the correct numeral.
- Large numbersSupports numbers from 4,000 to 3,999,999 using the overline (vinculum) notation.
- Date converterWrite any date in Roman numerals in day-month-year, month-day-year or year-month-day order.
The seven Roman numerals
| Symbol | I | V | X | L | C | D | M |
|---|---|---|---|---|---|---|---|
| Value | 1 | 5 | 10 | 50 | 100 | 500 | 1,000 |
How Roman numerals work
- Add when a symbol is followed by an equal or smaller one: VI = 5 + 1 = 6, XX = 20, LXX = 70.
- Subtract when a smaller symbol comes before a larger one: IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900.
- Only these six subtractive pairs are standard. 99 is XCIX (90 + 9), not IC.
- Don’t repeat a symbol more than three times: 4 is IV, not IIII; 40 is XL, not XXXX.
- V, L and D are never repeated and never used for subtraction.
The largest number in standard notation is 3,999 (MMMCMXCIX). For bigger numbers, a bar over a numeral multiplies it by 1,000, so V̅ is 5,000 and X̅ is 10,000.
Examples
| Number | Roman numeral | Breakdown |
|---|---|---|
| 14 | XIV | X + IV |
| 49 | XLIX | XL + IX |
| 500 | D | D |
| 1994 | MCMXCIV | M + CM + XC + IV |
| 2026 | MMXXVI | M + M + X + X + V + I |
| 3999 | MMMCMXCIX | MMM + CM + XC + IX |
Where Roman numerals are used today
You’ll find them on clock faces, in book chapters and prefaces (often in lowercase: i, ii, iii), in the names of monarchs and popes (Elizabeth II), for events like the Super Bowl and the Olympic Games, in film copyright dates, building cornerstones and, increasingly, in tattoos of meaningful dates. On clocks, 4 is often written as IIII for visual balance, a traditional exception.
There is no Roman numeral for zero, and the Romans didn’t write fractions this way. For writing numbers in words instead, try the Number to Words converter.
Frequently asked questions
How do you write 2026 in Roman numerals?+
2026 is MMXXVI: MM (2000) + XX (20) + VI (6).
What is the largest Roman numeral?+
In standard notation, 3,999 (MMMCMXCIX). Larger numbers use a bar over numerals to multiply by 1,000; this tool supports up to 3,999,999.
Why is 4 written as IV and not IIII?+
Standard Roman numerals use subtraction: I before V means 5 − 1. IIII appears on some clock faces as a traditional style choice.
Is there a Roman numeral for zero?+
No. The Romans had no numeral for zero; the word “nulla” was sometimes used instead.
How do I write a date in Roman numerals?+
Open “Convert a date”, pick the date and order. For example, 28 October 2026 is XXVIII.X.MMXXVI.