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Converter

Roman numeral converter

Convert integers from 1–3999 to canonical Roman numerals and back.

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Less switching. More focus.Functional build · Validation in progress

Using this tool

Encode and decode integers from 1–3999 as canonical Roman numerals.

Actions: Encode · Decode

Example

Choose Encode: 1994 becomes MCMXCIV using subtractive notation.

Example action and settings

Action: Encode

Input / action

1994

Result / expected behavior

MCMXCIV

Scope and limitations

  • Zero, negatives, fractions and values above 3999 are unsupported.

Common mistakes

  • Decoding requires canonical notation: use XCIX for 99, not IC.

Related tools

Integer base converter

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