IX
IX is a single Roman symbol group for 9. It uses subtractive notation: IX (10 - 1).
IX is a single Roman symbol group for 9. It uses subtractive notation: IX (10 - 1).
The number 9 is written IX in Roman numerals. Roman numerals use seven letters — I (1), V (5), X (10), L (50), C (100), D (500) and M (1000) — combined from largest to smallest, with subtractive pairs such as IV (4) and IX (9). Need another number? Use the Roman numeral converter or see the 1–100 chart.