Roman Numeral Converter
Two-way conversion between standard Arabic numbers and Roman numerals with step-by-step arithmetic breakdown.
Client-side calculations and instant parameter controls are initializing. All processing occurs securely in your browser.
How to Use the Roman Numeral Converter
- 1 Select conversion mode: Number to Roman Numeral or Roman Numeral to Number.
- 2 Enter a standard integer (1 - 3,999,999) or Roman letters (e.g. MMXXVI, XIV).
- 3 View the converted result and the additive/subtractive arithmetic breakdown.
Mathematical Formula & Principle
Subtractive & Additive Radix Translation (M=1000, D=500, C=100, L=50, X=10, V=5, I=1)
Calculations are performed with IEEE floating point mathematical precision directly in your device memory.
Worked Examples
Year 2026 Conversion
M (1000) + M (1000) + X (10) + X (10) + V (5) + I (1) = 2026.
Frequently Asked Questions
- What is the highest number you can write in standard Roman numerals?
- Standard Roman numerals go up to 3,999 (MMMCMXCIX). With extended vinculum rules, millions can also be represented.
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