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📅 Leap Year Calculator

Check if a year is a leap year, list leap years in a range, with step-by-step rule verification and statistics.

Check if a year is a leap year with rule breakdown, nearby leap years, and zodiac.

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Free online leap year calculator with two modes: single year check (rule breakdown, previous/next leap year, zodiac) and range query (leap year list, color-coded grid, statistics). Covers years 1–9999 for calendar lookup and math education.