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A Roman numeral date converter translates calendar dates into Roman numeral notation (e.g. IX·IV·MMXXVI) and vice versa. It is used for inscriptions, cornerstones, clock faces, and formal documents.

ステップバイステップガイド

1. 1Split date into day, month, and year components
2. 2Convert each number using Roman numeral subtraction rule: IV=4, IX=9, XL=40, XC=90, CD=400, CM=900
3. 3Combine with separator dots, hyphens, or slashes per tradition

解いた例

避けるべきよくある間違い

• ✕Using IIII instead of IV (clock faces use IIII but standard notation uses IV)
• ✕Forgetting that Roman numerals have no zero — year must be at least 1