Roman Numeral ↔ Decimal Converter
Free online Roman numeral converter. Convert between Roman numerals and decimal numbers instantly. Supports values 1 to 3,999,999.
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Tip: Valid Roman numerals: I(1), V(5), X(10), L(50), C(100), D(500), M(1000). Supports up to 3,999.
💡 Definition
Roman Numerals
- Roman numerals originated in ancient Rome and use combinations of letters (I, V, X, L, C, D, M) to represent values.
- They follow subtractive notation: IV = 4 (5−1), IX = 9 (10−1), XL = 40, XC = 90, CD = 400, CM = 900.
📖 How to use
Step by Step
- Enter a number (1–3,999) on the left
- The Roman numeral appears on the right
- Or enter a Roman numeral to get its decimal value
- Input is case-insensitive
🎯 Use cases
When to use
- Clock faces and watches
- Book chapters and outlines
- Movie and Super Bowl numbering
- Historical dates and inscriptions
Frequently Asked Questions
What is 2024 in Roman numerals?▾
2024 in Roman numerals is MMXXIV. MM = 2000, XX = 20, IV = 4.
What is the largest Roman numeral?▾
Standard Roman numerals go up to 3,999 (MMMCMXCIX). For larger numbers, a bar notation (vinculum) was used where a bar over a numeral multiplies it by 1,000.