Roman numerals
Conversion stays in this tab. Nothing is uploaded.
How to use this tool
Convert 1–3999 to standard Roman numerals, or valid Roman back to a number.
Open Roman numerals
A sample year is already converted. Direction sits on the left.
Enter a number or a numeral
IV is 4. Additive IIII is rejected. The range stops at 3999.
Copy the result
Copy puts the converted value on the clipboard. Nothing is uploaded.
FAQ
Can I convert Roman numerals here?
Yes. Numbers 1 to 3999 become standard subtractive Roman, and valid Roman becomes a number.
Is this uploaded?
No. Conversion stays in this tab.
Why is IIII invalid?
This tab uses the common form IV for 4. Additive IIII is rejected.
What about 4000?
Standard Roman here stops at 3999 (MMMCMXCIX).
Can I copy the result?
Yes. Copy puts the converted value on the clipboard.