Roman Numeral Converter (Advanced)
Convert between Roman numerals and decimals with vinculum support
About this tool
Bidirectional converter for Roman numerals and decimal numbers supporting values up to 4,999,999 using vinculum notation (a bar over a numeral multiplies it by 1,000). Type a decimal to get the Roman numeral or type Roman numerals to get the decimal value. A history of your last 10 conversions is saved locally, and a full reference table of all Roman symbols and their values is always visible below.
How to use
- 1 Type a decimal number (1–4,999,999) in the left field to convert to Roman numerals.
- 2 Or type Roman numeral characters in the right field to convert to decimal.
- 3 Numbers above 3,999 use vinculum notation shown with an overline.
- 4 Review the full symbol table at the bottom for a quick reference guide.
Frequently Asked Questions
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