Days Calculator
Pick two dates and get the full picture: total days, how many weeks that is, how many of them are business days, the inclusive count and the same gap expressed in years, months and days.
How to count days between two dates
There are two conventions. The exclusive count — what this calculator shows as the main figure — subtracts the dates directly: from January 1 to January 2 is 1 day. The inclusive count adds one so both endpoints are inside the interval; contract clauses that say "within 10 days including the start date" use this one.
Both numbers appear side by side in the result, so you never have to guess which one a deadline means. The calendar breakdown underneath expresses the same gap as years, months and days — the way rental agreements and ages are usually written.
Business days, and why they differ
Business days count Monday to Friday only and skip Saturdays and Sundays. A 30-day calendar span usually contains 20 to 23 business days, depending on where the weekends fall. Public holidays are not deducted — every country has its own calendar, so add them mentally if your deadline does.
If the end date is earlier than the start date the total turns negative and the calculator silently works with the reversed pair — the arrow in the subtitle shows the actual direction, and the swap button fixes it in one click.
Common uses
Contracts and notice periods. Notice, delivery and payment windows are usually calendar days — check whether the clause counts inclusively.
Project planning. Translate a calendar duration into business days to see how many working mornings a task really has.
Everyday questions. Days until a birthday or holiday, days since a purchase within the return window, or how long until the end of the month — the month-end button fills that in instantly.
Frequently asked questions
Does the main number include both dates?
No — it is the direct difference: January 1 to January 2 counts as 1 day. The inclusive figure, which counts both endpoints, is shown separately in the result.
How are business days calculated?
Mondays through Fridays only, starting at the start date and stopping before the end date. Public holidays are not deducted, because they differ by country.
What happens if I put the dates in the wrong order?
The total becomes negative, which is a useful signal in itself. The calculator computes with the reversed pair so the breakdown stays meaningful, and one click on Swap fixes the order.
Is the calendar breakdown the same as dividing by 30?
No. Years, months and days are counted the way calendars actually work — with variable month lengths and leap years — exactly like the age you would read off a birth certificate.
Can I count across years?
Yes, any span works, including multi-year ranges. The breakdown will show full years plus the remaining months and days.
Can I share a link to a specific pair of dates?
Yes — both dates travel in the URL, so a bookmarked or shared link reopens the exact calculation.