Roman numerals converter
Convert numbers to Roman numerals and back (1 to 3999).
How the calculation works
The Roman system uses seven letters with fixed values:
I = 1 · V = 5 · X = 10 · L = 50 · C = 100 · D = 500 · M = 1000
Two rules
- Addition: equal or decreasing symbols add (VI = 6). A symbol repeats at most 3 times (III = 3).
- Subtraction: a smaller symbol before a larger one subtracts (IV = 4, IX = 9, CM = 900).
Step-by-step example (2026)
2026 = 1000 + 1000 + 10 + 10 + 5 + 1 = MMXXVI.
Range
The classic system goes from 1 to 3999. There is no zero or negative in Roman numerals.
Examples
- 49 = XLIX (XL = 40, IX = 9).
- 2024 = MMXXIV.
Frequently asked questions
How do you write 2026?
MMXXVI (1000+1000+10+10+5+1).
Why is 4 IV and not IIII?
By the subtraction rule and to avoid repeating a letter 4 times. (Clocks sometimes use IIII by tradition.)
Is there a zero in Roman numerals?
No. The Roman system has no symbol for zero or negative numbers.
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Updated on June 18, 2026 · by Rafael Rossi · Methodology & sources