9 in Roman numerals
IX
The number 9 is written IX in Roman numerals.
How IX breaks down
| Symbols | Value |
|---|---|
IX | 9 |
IX | 9 |
This numeral uses the subtractive rule: a smaller symbol placed before a larger one is subtracted from it. Only six such pairs are legal — IV (4), IX (9), XL (40), XC (90), CD (400) and CM (900).
Nearby numbers
| Number | Roman numeral |
|---|---|
| 4 | IV |
| 5 | V |
| 6 | VI |
| 7 | VII |
| 8 | VIII |
| 9 | IX |
| 10 | X |
| 11 | XI |
| 12 | XII |
| 13 | XIII |
| 14 | XIV |
The seven symbols
I | 1 | C | 100 |
V | 5 | D | 500 |
X | 10 | M | 1,000 |
L | 50 |
9 in other notations
| Roman | IX |
| Binary | 1001 |
| Hexadecimal | 9 |
| Octal | 11 |
| Written out | nine |
Writing it by hand
Work down through the symbol values, taking as many of each as will fit before moving to the next. For 9:
IX = 9 remaining: 0The result reads IX — 2 characters, against 1 digit in Arabic numerals.
Frequently asked questions
What is 9 in Roman numerals?
IX
How do you read IX?
Work left to right, adding each symbol — except where a smaller symbol precedes a larger one, in which case it is subtracted. IX is 9.
How do you write 9 in words?
nine.
Why is there no zero?
Roman numerals have no symbol for zero. The concept reached Europe only with Hindu-Arabic numerals, centuries after the system was in use — which is a large part of why it was eventually replaced for arithmetic.