Roman Numeral Converter
Convert between Roman and Arabic numerals
What is Roman Numeral Converter?
A Roman numeral converter detects the direction automatically: hand it an integer and it returns Roman numerals, hand it Roman numerals and it returns an integer, one value per line for bulk conversion. Standard notation covers 1 through 3999. Conversion happens locally in your browser.
How to use Roman Numeral Converter
- 1Enter one integer or Roman numeral per line.
- 2The tool detects the direction and converts automatically.
- 3Copy the result.
Frequently asked questions
Why does it only go up to 3999?+
The largest standard Roman symbol is M for 1000. Anything from 4000 upwards needs a vinculum — an overbar meaning "multiply by a thousand" — which cannot be represented accurately with ordinary characters, so general-purpose implementations cap out at 3999.
IIII or IV for four — which one is correct?+
IV, using subtractive notation, is the standard form. IIII is a historical variant that still survives on some clock faces. This tool always generates the standard form, and when parsing it accepts IIII and similar non-standard spellings by simply adding the values together.
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