Date Info (Weekday, Week, Quarter, Leap Year)
Local ProcessingWeekday, day and week of the year, quarter, leap year, first and last day and length of the month for a date.
How It Works & Processing Standards
Weekday, day and week of the year, quarter, leap year, first and last day and length of the month for a date.
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Current Limits
- Maximum input length: 100,000 characters
Pick common date facts from one "Task" list. Weeks follow ISO 8601 (starting Monday), so early and late weeks can belong to the previous or next year.
What You Can Do
- Weekday and day of year
- The weekday, the day number in the year and days remaining.
- ISO week
- Which week it is, or which dates "2026 week 1" covers.
- Quarter and month
- Quarter and its bounds, first and last day, days in month, a month table.
- Leap year
- Whether the year is leap, February length and days in the year.
How to Use Date Info (Weekday, Week, Quarter, Leap Year)
- 1Choose a taskPick what you want to know.
- 2Enter date or yearA date, or year, week, quarter or month depending on the task.
- 3Read the resultSee the answer.
Examples
Common Use Cases
- Matching week numbers in weekly reports
- Checking quarter-end or month-end dates
- Seeing which weekday a birthday or anniversary falls on
Frequently Asked Questions (FAQ)
Why does 2026 week 1 start in December 2025?
ISO week 1 is the week containing the first Thursday of the year. 1 January 2026 is a Thursday, so week 1 starts on Monday 29 December 2025.
2100 is divisible by 4 — why is it not a leap year?
Years divisible by 100 are not leap years unless also divisible by 400. So 2000 was a leap year and 2100 is not.