Roman Numeral Converter
Convert between Arabic numbers (1-3999) and Roman numerals instantly. See step-by-step breakdown of conversions, reference chart of Roman numeral values, and common examples. Perfect for learning, dates, and document formatting.
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How to Use
Select conversion mode
Choose 'Arabic to Roman' to convert numbers like 2024 to MMXXIV, or 'Roman to Arabic' to convert numerals like MCMXCIX to 1999.
Enter your number or numeral
Type a number between 1 and 3999, or enter a Roman numeral. The tool accepts both uppercase and lowercase Roman numerals.
View the conversion breakdown
See how the conversion works step-by-step. For example, 2024 breaks down as 2000(MM) + 20(XX) + 4(IV) = MMXXIV.
Copy or reference examples
Copy the result to your clipboard or use the reference chart and common examples to learn Roman numeral patterns.
Frequently Asked Questions
Why do Roman numerals only go up to 3999?
Standard Roman numerals have no symbol for 5000 or higher. The number 3999 (MMMCMXCIX) is the maximum using conventional symbols. While extended notations exist (using bars over letters to multiply by 1000), 3999 is the conventional limit.
What is subtractive notation in Roman numerals?
Placing a smaller numeral before a larger one indicates subtraction. For example, IV=4 (5-1), IX=9 (10-1), XL=40 (50-10), XC=90 (100-10), CD=400 (500-100), CM=900 (1000-100). This makes numerals shorter than repeating symbols.
Are lowercase Roman numerals valid?
Yes, Roman numerals can be written in uppercase (IV) or lowercase (iv). Uppercase is more common in formal contexts, while lowercase is often used in outlines and pagination (i, ii, iii). This tool accepts both.
How do I read a year like MMXXIV?
Break it down by position: MM=2000 (two thousands), XX=20 (two tens), IV=4. Total: 2024. Each symbol adds to the total unless it precedes a larger symbol (subtractive notation).