How to calculate the days between two dates?
Our days between dates calculator shows the exact difference between any pair of dates in multiple units: days, weeks, months, years, hours, and even business days.
Calculation formula
Days = End date − Start date Weeks = Days ÷ 7 Months = Calendar month difference (with day adjustment)
Types of calculations available
Calendar days
Counts every day including Saturdays and Sundays. Useful for:
- Calculating pregnancy timelines
- Determining time between events
- Counting days to personal goals
Business days
Counts only Monday through Friday. Important for:
- Work deadlines
- Banking calculations
- Legal and judicial deadlines
- Deliveries and shipments
Weeks and months
- Weeks: days divided by 7, showing full weeks and remaining days
- Months: precise calculation considering each month's variable length
By default, the calculator does not include the end date (like a stopwatch: Monday to Friday is 4 days). Turn on "Include end date" if you need to count both endpoints, such as when calculating vacation days (Monday to Friday = 5 days).
Useful date facts
| Period | Days | Weeks | |---|---|---| | 1 average month | 30.44 | 4.35 | | 1 quarter | 91 | 13 | | 1 half-year | 182 | 26 | | 1 year | 365 | 52.14 | | 1 leap year | 366 | 52.29 |
Leap years have 366 days (February has 29 days). They occur every 4 years, except years divisible by 100, unless also divisible by 400. Examples: 2024 and 2028 are leap years; 1900 was not; 2000 was.
Common uses
- Pregnancy: how many weeks have passed since conception?
- Legal deadlines: how many business days are left to submit a document?
- Projects: how many weeks until the delivery date?
- Birthdays: how many days until your birthday?
- Travel: how many days does your trip last?
Subtract the start date from the end date. Our calculator counts exact calendar days. You can also choose to include or exclude the end date and see the result in weeks, months, hours, or business days automatically.
Business days are Monday through Friday, excluding weekends. They are essential for work, banking, and legal calculations. A typical month has between 20 and 23 business days.
A regular year has 365 days. A leap year has 366 days (February has 29 days instead of 28). Leap years occur every 4 years, with exceptions for centuries.
Divide the total number of days by 7. For example: 45 days = 6 weeks and 3 days. Our calculator does this automatically and shows full weeks plus remaining days.
It depends on the month and year. A typical month has between 20 and 23 business days. February usually has 20 business days, while 31-day months can have up to 23.
By default, the calculator does not include the end date in the count (standard difference counting). You can enable "Include end date" if you need to count both endpoints, such as when calculating vacation days.
The calculator counts Monday through Friday as business days. It does not subtract national holidays, since they vary by country. For more precise calculations, manually subtract your country's holidays.
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- Date calculator: add and subtract days from a date
- Age calculator: years, months, and days since birth
- Time zones: convert times between timezones for scheduling