9 in Roman Numerals
9 in Roman numerals is IX. It is built from one part: 9 = IX. Read it from left to right and add the values to get 9. Copy it below, see why it is written this way, and check the numbers before and after. The converter handles any number from 1 to 3,999.
9 in Roman numerals is IX.
9 in Roman numerals: the breakdown
| Place value | Numeral | Value |
|---|---|---|
| 9 | IX | 9 |
| Total | IX | 9 |
9 is a single place value, so IX on its own is 9.
Why IX and not VIIII?
IX uses the subtractive pair IX. Written by adding only, 9 would be VIIII, but a letter may repeat only three times in a row, and VIIII repeats I four times.
How to read IX
- IX is 10 minus 1, which is 9.
- There is nothing else to add, so IX is 9.
The numbers around 9
Facts about 9
- 9 is an odd number.
- 9 is not prime: 9 = 3 x 3.
- 9 is a perfect square: 3 x 3 = 9.
- The digits of 9 add up to 9.
- IX is 2 letters long. It uses the symbols X and I.
Convert another number
What number is IX?
IX is the number 9. It is a single place-value part, so reading it from left to right gives 9 straight away.
Questions and answers
What is 9 in Roman numerals?
9 in Roman numerals is IX. It is made of one part: 9 = IX. Read IX from left to right, add the parts, and you get 9. Use the converter on this page to check any other number from 1 to 3,999.
How do you write 9 in Roman numerals?
Split 9 into its place values, write each one in Roman numerals, and join them from largest to smallest. For 9 there is only one place value, so the answer is IX. Check that no letter repeats more than three times in a row.
What number is IX?
IX is 9. Read it from left to right: it is a single place-value part, IX, which is 9, so there is nothing else to add. Letters after a larger or equal letter are added, and a smaller letter before a larger one is subtracted. You can also type IX into the converter to read the number back.
Why is 9 written IX and not VIIII?
IX is the standard form. VIIII breaks a rule: a letter may repeat only three times in a row, and VIIII repeats I four times. Writing IX keeps every letter within those limits and makes 9 easy to read at a glance.