➗ Roman Numeral Converter — 1 to 3999
Turn an integer into a standard Roman numeral, or paste a numeral such as MCMXCIV and get the integer. Subtractive pairs are validated.
Input
Result
Summary
Private by design. This tool runs entirely in your browser — nothing you enter or add is uploaded to any server.
How it works
- Enter an integer from 1 to 3999, or a Roman numeral using I, V, X, L, C, D and M.
- Choose a direction and press Convert.
- Invalid repeats and non-standard subtractive pairs are rejected.
Examples
- 1994 becomes MCMXCIV.
- XLII becomes 42.
- IIII is rejected because four repeats are not standard.
Frequently asked questions
Why stop at 3999?
Standard Roman numerals without overlines cover 1 through 3999. Larger values need vinculum notation, which this tool does not emit.
Is IIII accepted for clocks?
No. Only the standard subtractive form is accepted, so 4 is IV.
Is the value uploaded?
No. Conversion runs in the browser.
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