Days between two dates calculator
Work out the exact number of days between two dates: calendar days or business days. With "+1 day" and period-overlap options for error-free planning.
Pick two valid dates to see the result.
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No more mental-math mistakes
Counting the number of days between two dates on your fingers always ends in an error. Do you count the first day? What about leap years? One day late on a contract clause or a delivery is already too much. Our calculator does the maths for you: you instantly get the exact gap in days, weeks, months and years, with no approximation.
Calendar days vs business days
Calendar days
Monday to Sunday, weekends included. This is the default view, ideal for rent or a subscription.
Business days
Tick the option and the algorithm automatically removes Saturdays and Sundays to give the real working time.
The "+1 day" trap (end day included)
Between the 1st and the 3rd of the month, there are mathematically 2 days of difference (3 − 1 = 2): that's the raw duration. But if you rent equipment from the 1st to the 3rd inclusive, you actually pay for the 1st, 2nd and 3rd — three full days. The +1 day option fixes this nuance, turning a simple mathematical gap into a real action duration.
FAQ
How do I calculate business days between two dates?
Enter your start and end dates, then tick the "Business days" option. The algorithm automatically excludes all weekends to give you the net number of working days.
Does the tool account for leap years?
Yes. The calculator relies on the real calendar. February 29th is fully counted if your date range spans a leap year.
Are public holidays removed from the business-days calculation?
No. The "business days" feature only removes weekends. Public holidays vary by country, agreement and region, so they must be subtracted manually from your result.
How can I check whether two periods overlap?
Turn on the "Compare 2 periods" option. Enter your two date ranges (for example your accommodation booking and your flight tickets) and the tool shows exactly how many days they overlap.
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