Roman numerals converter

Numbers to numerals and back, with the canonical subtractive form, the place-by-place construction, and honest validation: IIII is accepted and explained, IL is refused with the rule it breaks.

Documentation (Markdown)

Encoding & data

Documentation

Number or numeral

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API endpointGEThttps://ronutz.com/api/v1/roman-numeralsDocumented, not served. Opens the specification.

References

Encyclopaedia Britannica — Roman numeral
Unicode — Number Forms block (Roman numeral characters)
Library of Congress — Why do clock faces use IIII?