Roman Numerals Converter — Numbers ↔ Roman Numerals Free Online
Convert any number (1–3999) to Roman numerals — or decode any Roman numeral back to a number — instantly. Includes a step-by-step breakdown, full chart, common year lookups, and rules guide.
⚡ Instant conversion — runs entirely in your browser.
📊 Roman Numerals Reference Chart
| Roman | Value | Roman | Value |
|---|---|---|---|
| I | 1 | L | 50 |
| IV | 4 | XC | 90 |
| V | 5 | C | 100 |
| IX | 9 | CD | 400 |
| X | 10 | D | 500 |
| XL | 40 | CM | 900 |
| I–III | 1–3 | M | 1000 |
| VIII | 8 | MMM | 3000 |
What Are Roman Numerals?
Roman numerals are a numeral system originating in ancient Rome that uses combinations of seven Latin letters to represent numbers: I (1), V (5), X (10), L (50), C (100), D (500), and M (1000). They were the standard writing system for numbers across Europe for well over a millennium and are still widely used today — on clock faces, in movie credits, book chapters, Super Bowl numbering, Olympic Games, and formal document pagination.
The system uses both additive and subtractive notation. Additive: VIII = 5 + 3 = 8. Subtractive: IX = 10 − 1 = 9. The subtractive rule prevents four identical symbols from appearing consecutively: 4 is IV, not IIII; 9 is IX, not VIIII.
How to Convert Numbers to Roman Numerals
Break down the number by place value — thousands, hundreds, tens, ones.
Match each part to the Roman numeral table. 2000 = MM, 500 = D, 90 = XC, 6 = VI.
Concatenate the parts from largest to smallest. 2596 = MM + D + XC + VI = MMDXCVI.
Roman Numeral Rules — Quick Reference
- ✓Repeat up to 3 times: I, X, C, M can repeat (III = 3, XXX = 30). V, L, D are never repeated.
- ✓Subtractive pairs: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900. These are the only valid subtractive combinations.
- ✓Descending order: Always write from highest to lowest value, left to right (except subtractive pairs).
- ✓Max value: Standard Roman numerals only go up to 3999 (MMMCMXCIX) without special notation.
Frequently Asked Questions
What is MMXXVI in numbers?
MMXXVI = 2026. MM = 2000, XX = 20, VI = 6.
How do you write 2024 in Roman numerals?
2024 in Roman numerals is MMXXIV. MM = 2000, XX = 20, IV = 4.
What is the Roman numeral for 1000?
The Roman numeral for 1000 is M. 2000 = MM, 3000 = MMM.
Why is 4 written as IV and not IIII?
To avoid repeating a character four times, the subtractive rule is used: I placed before V means V−I = 4. The same logic applies to IX (9), XL (40), XC (90), CD (400), and CM (900).
What is the largest number in Roman numerals?
The standard maximum is 3999 (MMMCMXCIX). Historical texts used a bar (vinculum) over numerals to multiply by 1000, allowing much larger numbers.
What year is it in Roman numerals?
2026 in Roman numerals is MMXXVI.