Date Calculator
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History of the Gregorian Calendar
The Gregorian calendar is the most widely used calendar today. A typical year has 365 days, and a leap year has 366 with an extra day added to February.
It replaced the Julian calendar to correct discrepancies between the calendar year and the solar year. In 1582, Pope Gregory XIII advanced the calendar by 10 days to realign it with the equinox.
Century years are only leap years if divisible by 400 (e.g., 2000 was a leap year, 1900 was not).
Holidays
Holidays vary across regions and cultures. In the U.S., “holidays” typically refer to nationally recognized days like Thanksgiving and Independence Day.
Federal holidays in the U.S. mean paid leave for government employees. Private sector employees may receive holidays based on company policy.
2025 U.S. Federal Holidays
- New Year’s Day – Jan 1
- Memorial Day – May 26
- Independence Day – Jul 4
- Labor Day – Sep 1
- Thanksgiving – Nov 27
- Christmas – Dec 25
2026 U.S. Federal Holidays
- New Year’s Day – Jan 1
- Memorial Day – May 25
- Independence Day – Jul 4
- Labor Day – Sep 7
- Thanksgiving – Nov 26
- Christmas – Dec 25
📅 About the Gregorian Calendar
The Gregorian calendar, used worldwide today, consists of 365 days in a year, with an extra day added in February during leap years (making it 29 days). Most months have 30 or 31 days, except for February.
It replaced the Julian calendar, which misaligned with the solar year over time. To fix this, Pope Gregory XIII introduced reforms in 1582, including:
- Skipping 10 days (Oct 4 → Oct 15, 1582)
- Updating leap year rules: only century years divisible by 400 are leap years (e.g., 2000, but not 1900)
These changes made the calendar much more accurate and it remains the global standard today.
🎉 Holidays Overview
Holidays are special days set aside for rest or celebration. While some like New Year’s Day or Christmas are globally recognized, many are unique to each country or culture. In the U.S., federal holidays mean paid leave for government employees, though private companies may vary.
Some holidays have fixed dates (e.g., Dec 25), while others float (e.g., Thanksgiving falls on the 4th Thursday of November).
You can manually add or exclude holidays in the calculator for custom results.
🗓 U.S. Federal Holidays (2025–2026 Highlights)
- New Year’s Day – Jan 1
- Independence Day – Jul 4
- Labor Day – 1st Mon of Sep
- Thanksgiving – 4th Thu of Nov
- Christmas Day – Dec 25