Which symbols are used?

The seven Roman letters: I (1), V (5), X (10), L (50), C (100), D (500), and M (1000), combined to form any value in range.

How are 4 and 9 written?

With subtractive notation: 4 is IV (one before five) and 9 is IX (one before ten), rather than IIII or VIIII.

1 to 3999. There is no Roman symbol for zero, and larger numbers require notation beyond the standard letters.

Yes. Translating between Arabic and Roman numerals happens in your browser; nothing you enter is transmitted.

Converters

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Convert between Arabic numbers and Roman numerals instantly, free and in your browser. Supports values from 1 to 3999 with no account required.

Arabic number (1–3999)

Roman numeral

Which symbols are used?: The seven Roman letters: I (1), V (5), X (10), L (50), C (100), D (500), and M (1000), combined to form any value in range.
How are 4 and 9 written?: With subtractive notation: 4 is IV (one before five) and 9 is IX (one before ten), rather than IIII or VIIII.
What is the supported range?: 1 to 3999. There is no Roman symbol for zero, and larger numbers require notation beyond the standard letters.
Is the conversion done privately?: Yes. Translating between Arabic and Roman numerals happens in your browser; nothing you enter is transmitted.