Convert between Roman numerals and decimal numbers instantly, with validation and step-by-step breakdown of numeral values.
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Number Systems
The Roman numeral converter translates numbers between standard Roman numeral notation and decimal (Arabic) form. Enter a Roman numeral or a decimal number and get the equivalent value instantly.
Roman numerals use seven symbols: I (1), V (5), X (10), L (50), C (100), D (500), and M (1000). When a smaller-value symbol appears before a larger one, it is subtracted. Otherwise symbols are added left to right.
Standard form limits repetition to three consecutive identical symbols and uses specific subtractive pairs: IV, IX, XL, XC, CD, and CM.
Roman numerals still appear on clock faces, book chapter headings, movie sequel titles, and Super Bowl numbering. Understanding the system helps interpret these everyday uses and historical dates inscribed on buildings.
Frequently asked questions
Standard notation goes up to 3999 (MMMCMXCIX). Larger values historically used overline notation, but these are rarely encountered today.
No. The Roman system has no symbol for zero. The concept of zero was introduced later through the Hindu-Arabic numeral system.
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