Three quizzes
- Roman → number – a Roman numeral appears (XLIV, for example) and you type its value. After each answer the game shows it place by place: XL (40) + IV (4).
- Number → Roman – write a number in Roman numerals. On mobile you can use the on-screen I, V, X, L, C, D, M buttons.
- Years – famous dates written the way you see them on monuments and film credits: which year is MCMLXIX?
Pick a range: 1–50, 1–500 or 1–3999. About half of every round contains a 4 or a 9, because that is where you have to subtract – and where most mistakes happen. Each round ends with a grade, and you can replay just the ones you got wrong.
Roman numeral symbols
| Symbol | I | V | X | L | C | D | M |
|---|---|---|---|---|---|---|---|
| Value | 1 | 5 | 10 | 50 | 100 | 500 | 1000 |
The rules in short
- Add: when the symbols go down in size from left to right (or stay the same), add them: VI = 6, XXV = 25, MDC = 1600.
- Subtract: when a smaller symbol stands before a larger one, subtract it: IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900.
- At most three in a row: III = 3, but 4 = IV.
- V, L and D never repeat and are never subtracted: 10 = X (not VV), 95 = XCV (not VC).
- Work place by place. Split the number into thousands, hundreds, tens and ones and write each separately: 1994 = 1000 + 900 + 90 + 4 = M CM XC IV = MCMXCIV.
Roman numerals chart
| Ones | Tens | Hundreds | Thousands |
|---|---|---|---|
| 1 = I | 10 = X | 100 = C | 1000 = M |
| 2 = II | 20 = XX | 200 = CC | 2000 = MM |
| 3 = III | 30 = XXX | 300 = CCC | 3000 = MMM |
| 4 = IV | 40 = XL | 400 = CD | |
| 5 = V | 50 = L | 500 = D | |
| 6 = VI | 60 = LX | 600 = DC | |
| 7 = VII | 70 = LXX | 700 = DCC | |
| 8 = VIII | 80 = LXXX | 800 = DCCC | |
| 9 = IX | 90 = XC | 900 = CM |
Any number can be built from these four columns: 2026 = MM + XX + VI = MMXXVI.
Years in Roman numerals
Years are written the same way, place by place. A few you will meet often:
| Year | Roman numerals | Breakdown |
|---|---|---|
| 1066 | MLXVI | M + LX + VI |
| 1492 | MCDXCII | M + CD + XC + II |
| 1776 | MDCCLXXVI | M + DCC + LXX + VI |
| 1969 | MCMLXIX | M + CM + LX + IX |
| 1990 | MCMXC | M + CM + XC |
| 1999 | MCMXCIX | M + CM + XC + IX |
| 2000 | MM | M + M |
| 2026 | MMXXVI | MM + XX + VI |
Frequently asked questions
How do you write 4 and 9 in Roman numerals?
4 = IV (5 − 1) and 9 = IX (10 − 1). When a smaller symbol stands before a larger one, you subtract it. The same goes for 40 = XL, 90 = XC, 400 = CD and 900 = CM.
Why is 4 not written IIII?
The same symbol may appear at most three times in a row: III = 3, XXX = 30, CCC = 300. So 4 is written by subtraction: IV. (Some clock faces still show IIII, but IV is the standard form today.)
What is the largest number you can write in Roman numerals?
With the seven basic symbols (I, V, X, L, C, D, M) the largest is 3999 = MMMCMXCIX. The Romans wrote bigger numbers with a bar over a symbol, which multiplies it by 1000, but that is rarely used today.
How do you write years in Roman numerals?
Place by place: 1990 = 1000 + 900 + 90 = M + CM + XC = MCMXC. 2026 = MM + XX + VI = MMXXVI. This is how years appear on film credits, monuments and cornerstones.
What year is MCMLXIX?
MCMLXIX = M (1000) + CM (900) + LX (60) + IX (9) = 1969, the year Apollo 11 landed on the Moon.
Is there a zero in Roman numerals?
No. Roman numerals have no symbol for zero; they were used for counting and recording amounts, where zero was not needed.