Days Between Dates Calculator
Count the number of days, weeks, months and business days between two dates.
How days between dates are counted
The calculator subtracts the start date from the end date. By default it does not count the end date itself, which matches how most people count durations: from Monday to Tuesday is one day. Tick "include the end date" when you want to count both days, for example for the length of a hotel stay in nights versus days, or the number of days in a leave request.
From January 1 to March 1 in a common year is 31 + 28 = 59 days. In a leap year it is 60. Including the end date adds one more.
Business days
Business days (working days) count only Monday to Friday. The calculator removes Saturdays and Sundays automatically. Public holidays are not removed because they differ by country, state and employer; subtract them yourself if needed. In the US there are about 11 federal holidays a year, and in the UK around 8 bank holidays.
Days in each month
A quick way to remember: on your knuckles, every knuckle is a 31-day month and every gap between knuckles is a shorter month, starting with January on the first knuckle. February has 28 days, or 29 in a leap year. A year is a leap year if it divides by 4, except century years, which must also divide by 400. So 2000 was a leap year but 1900 was not.
Common uses
- Countdowns to holidays, weddings and exams.
- Notice periods, contract terms and payment deadlines.
- Project planning in working days.
- Calculating interest that accrues daily.
Frequently asked questions
How do I count days between two dates?
Subtract the earlier date from the later date. The calculator handles different month lengths and leap years for you.
Does the count include the start and end date?
By default it counts the start date but not the end date. Tick the option to include the end date.
Are holidays excluded from business days?
No. Only weekends are excluded, because holidays vary by location. Subtract any holidays that fall in your period.
Last reviewed Oct 20, 2026. Results are estimates; check important decisions with a qualified professional.