About the Days Between Dates Calculator
Sometimes you need a single, exact number: how many days until a holiday, how many days a guest stayed, how many days of interest a loan has accrued, how many days a project has run, or how many days are left in the year. The days between dates calculator counts the days between any two dates precisely, allowing for leap years and months of different lengths.
It also solves the most common source of confusion in day counting — whether to include the end date. You can count the gap between the dates, as for nights in a hotel, or count every calendar date in the range, as for days of an event. The calculator also splits the total into weekdays and weekend days and into weeks and days.
How to Use the Days Between Dates Calculator
Enter the start date and the end date.
Choose whether to include the end date in the count.
The number of days appears with the breakdown.
How the Days Are Counted
exclusive: days = end date − start date
(1 March to 3 March = 2 days)
inclusive: days = end date − start date + 1
(1 March to 3 March = 3 days: the 1st, 2nd and 3rd)Each date is converted to a day number and the numbers are subtracted, so month lengths and leap days are handled automatically.
Step-by-Step Example
From 1 January 2026 to 25 December 2026.
Exclusive: 358 days = 51 weeks and 1 day
Inclusive: 359 days
Weekdays: 256 Weekend days: 102 (exclusive count)There are 358 days from New Year's Day to Christmas Day 2026, not counting Christmas Day itself.
Inclusive or Exclusive: Which Do I Need?
Use the exclusive count — the default — for elapsed time. Nights in a hotel, interest on a loan, the length of a rental, the age of something and the time until an event are all measured this way. Checking in on the 1st and out on the 3rd is two nights.
Use the inclusive count when every calendar date is a separate unit. A festival running from the 1st to the 3rd lasts three days; a hospital stay from Monday to Wednesday may be charged as three days; a course of tablets taken from the 1st to the 10th lasts ten days. When in doubt, ask whether the last day "counts" in the situation you are measuring.
The Fencepost Problem
The inclusive-or-exclusive confusion is a classic example of what programmers call a fencepost error. A 30-metre fence with posts every 3 metres needs 11 posts, not 10, because there is a post at each end. In the same way, the dates 1 to 10 March contain ten dates but only nine one-day gaps. Most day-counting mistakes are off by exactly one, and almost always for this reason.
Weekdays and Weekends
The calculator counts how many of the days fall on Monday to Friday and how many on Saturday and Sunday. Over a long range the proportion is always close to five weekdays in seven, about 71 percent. Over short ranges it depends on where the range starts. The count does not remove public holidays; for working-day deadlines, use a business days calculator.
Leap Years
Because the calculator counts real calendar days, any range that includes 29 February of a leap year is automatically one day longer. From 1 January to 31 December is 364 days in a common year and 365 in a leap year (exclusive), or 365 and 366 inclusive. The next leap days are 29 February 2028 and 2032.
Counting Days Remaining
To find how many days are left in the year, enter today as the start date and 31 December as the end date with the end date included. To count down to an event, enter today and the event date without including the end date — the result is the number of "sleeps" until the day arrives.
Day Counts in Finance
Banks and lenders count days carefully because interest is often charged per day. A loan at a daily rate accrues interest for each day from the drawdown date up to, but not including, the repayment date — the exclusive count. Some financial markets use conventions such as "actual/365", which divides the actual number of days by 365, or "30/360", which pretends every month has 30 days. This calculator always gives the actual number of days, which is the starting point for any of these conventions.
Understanding Your Result
The headline is the number of days.
The how counted line says whether the end date was included.
The weekdays and weekends line splits the total.
The weeks line gives the total as weeks and days.
The other counting line gives the answer under the other convention.
When Should You Use This Calculator?
Use it to count days until a holiday, trip or deadline.
Use it to count nights stayed or days rented.
Use it to calculate daily interest or charges.
Use it to count days remaining in a year, term or contract.
Common Mistakes
Being off by one. Decide whether the end date should count.
Counting on your fingers across month ends. Months have 28 to 31 days.
Forgetting leap years. A range containing 29 February is a day longer.
Treating weekdays as working days. Public holidays are not removed.
Mixing up the date format. Enter dates as year-month-day.
Swapping the dates by mistake. The calculator reorders them, but check the range line to be sure the right dates were used.