Roman Numeral Converter
How to use this Roman numeral converter
- Type a number (1-3999) in the left field to get its Roman numeral.
- Or type a Roman numeral in the right field to get its numeric value.
- Both fields update live as you type in either direction.
How does Roman numeral notation work?
Roman numerals combine seven symbols (I, V, X, L, C, D, M) using an additive and subtractive system: symbols are added left to right, except when a smaller value precedes a larger one, which subtracts it (like IV = 4, meaning 5 minus 1).
Why can't I convert numbers above 3999?
Standard Roman numerals don't have a symbol for values above 1000 (M) beyond simple repetition, so 3999 (MMMCMXCIX) is the practical upper limit without special notation.
Is there a Roman numeral for zero?
No, the Romans had no symbol or concept of zero as a numeral in their system — it simply isn't representable.