Leap Year & Calendar Helper
Check if a year is a leap year and get calendar facts like day of week, week number, day of year, and more. Supports ISO-8601 and US week numbering rules.
Frequently Asked Questions
Check Leap Years and Calendar Facts Instantly
Enter a date to get day of week, week number, day of year, and more. Find out if a year is a leap year and explore calendar properties.
Leap Year Check
Verify if any year is a leap year using Gregorian rules
Day of Week
Find what day of the week any date falls on
Week Number
Get ISO or US-style week numbers for any date
Tip: The Gregorian leap year rule is: divisible by 4, except years divisible by 100, unless also divisible by 400.
Frequently Asked Questions
Understanding Leap Years & Calendar Facts
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