Roman Numeral Converter
Convert between Roman numerals and Arabic numbers. Perfect for dates, clock face...Convert between Roman numerals and Arabic numbers. Perfect for dates, clock faces, and historical research.
Arabic Number
Valid range: 1 - 3,999
Roman Numeral
Roman Numeral Reference
Subtractive Combinations
Common Conversions
Converter Features
Why Use Roman Numeral Converter?
Bidirectional Conversion
Convert Arabic numbers to Roman numerals or decode Roman numerals back to numbers.
Step-by-Step Breakdown
See exactly how each Roman numeral symbol contributes to the total value.
Complete Reference
Built-in reference chart with all 7 basic symbols and 6 subtractive combinations.
100% Private
All conversion happens in your browser. No data is transmitted to any server.
Validation
Detects non-standard Roman numeral formats and warns about potentially incorrect input.
Instant Results
Real-time conversion as you type with zero delay or processing time.
Common Uses for Roman Numerals
Dates & Years
Convert years for copyright notices, movie dates, and historical documents.
Clock Faces
Understand and verify Roman numeral positions on traditional clock dials.
Education
Learn Roman numeral rules with interactive conversion and step-by-step breakdowns.
History & Literature
Decode Roman numerals found in historical texts, monuments, and manuscripts.
How It Works
Choose Direction
Select 'Number to Roman' to encode or 'Roman to Number' to decode Roman numerals.
Enter Your Value
Type a number (1-3999) or Roman numerals (I, V, X, L, C, D, M). Results appear instantly.
View Breakdown & Copy
See the step-by-step conversion breakdown, then copy the result to your clipboard.
Tips & Information
Subtractive Rule
Remember: when a smaller numeral appears before a larger one, it's subtracted (IV=4, IX=9, XL=40, XC=90, CD=400, CM=900).
Year Conversion
To convert a year like 2024: break it into 2000 (MM) + 20 (XX) + 4 (IV) = MMXXIV.
Range Limit
Standard Roman numerals only cover 1-3999. Numbers outside this range cannot be accurately represented.