Roman Numerals Converter Online
Runs 100% in your browser — your files never leave your device.
Copyright lines, clock faces, chapter numbers, super bowls — roman numerals never quite go away. Type a decimal integer to get its roman form, or a roman numeral to get the integer; the converter detects the direction and validates canonical spelling (IIII is politely refused). Range 1–3999.
How it works
- 1
Type a number or numeral
A decimal integer or a roman numeral — direction is detected.
- 2
Read the conversion
The other form appears instantly, validated as canonical.
- 3
Copy the result
One click copies the converted value.
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