Roman Numeral Converter

Instantly convert numbers between the Roman and Arabic numeral systems, from 1 to 3999.

Enter a value in either field

The other field will update automatically.

Arabic Number

Roman Numeral

Start typing a valid number (1-3999) or Roman numeral in either field. The calculator will automatically convert it.

How to Use

To Convert from Arabic: Enter a number from 1 to 3999 in the "Arabic Number" field. The Roman numeral will appear automatically.
To Convert from Roman: Type a valid Roman numeral in the "Roman Numeral" field. The Arabic number will appear automatically.
Reset: Click the "Reset" button to clear both fields and start over.

Frequently Asked Questions