Roman Numeral Converter
Numbers to Roman numerals and back
Roman Numerals
How it's built
- MM + XX + VI = 2,000 + 20 + 6 = 2,026
- 1Choose a directionNumber → Roman or back
- 2Type the valueFrom 1 to 3,999
- 3See the conversionWith each part explained
How Roman numerals work
Seven letters stand for values. Write them largest first and add them up, except that a smaller letter before a larger one is subtracted.
I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1000
IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900
2026 = MM + XX + VI = MMXXVI
The subtraction rule
Only I, X and C are placed before a larger letter, and only before the next two sizes up: I before V and X, X before L and C, C before D and M. So 99 is XCIX, not IC.
Why stop at 3,999?
Standard Roman numerals use M for 1,000 and never repeat a letter more than three times, so MMMCMXCIX (3,999) is the largest. Bigger numbers used a bar over a letter to multiply it by 1,000.
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Frequently asked questions
What is 2026 in Roman numerals?
MMXXVI: MM (2000) + XX (20) + VI (6).
How do I write 4 in Roman numerals?
IV, meaning one less than five. You may see IIII on clock faces, but IV is the standard form.
Is there a Roman numeral for zero?
No. The Romans had no symbol for zero; the word nulla (“none”) was used instead.
Last reviewed: October 2026