About This Calculator
This Roman Numeral Calculator converts between Arabic numbers and Roman numerals. It supports values from 1 to 3999, following the standard Roman numeral rules. Both uppercase and lowercase Roman letters are accepted.
How to Use
- Select conversion mode: Number to Roman or Roman to Number.
- Enter a number (1–3999) or a Roman numeral using either uppercase or lowercase letters.
- Click "Convert" to see the result and breakdown table if applicable.
Frequently Asked Questions
Why is the maximum number 3999?
Standard Roman numerals use M (1000) up to three times. There is no standard symbol for 5000 or beyond without using nonstandard notation.
Is the conversion case-sensitive?
No. The calculator normalizes input to uppercase internally, so bothXIVandxivare accepted.
How accurate is the reverse conversion?
The calculator validates the Roman numeral and ensures it conforms to standard Roman syntax before converting.