What is a date difference calculator?
A date difference calculator measures the time between a start date and an end date. It’s handy for project deadlines, contract periods, pregnancy weeks, travel planning, notice periods or counting down to an event.
Results are shown several ways at once: total days, weeks and days, years-months-days, and the number of working days (Monday to Friday). You can choose whether the end day itself should be counted.
How to calculate the days between two dates
- 1
Choose the start date.
- 2
Choose the end date.
- 3
Tick “Include the end day” if the last day should count (for example, for hotel nights vs. full days).
- 4
Read the result in days, weeks, months and working days.
Features
Multiple formats
Total days, weeks + days, and years + months + days side by side.
Working days
Counts Monday–Friday business days for deadlines and payroll.
Inclusive option
Add the end day when you need to count both the first and last day.
Swap in one click
Entered the dates the wrong way round? Swap them instantly.
Examples
1 January to 31 December 2026
364 days between the dates, or 365 days if you include the end day.
Notice period
From 1 October to 31 October 2026 there are 30 days (31 if you include the end day), and 22 of them are working days Monday to Friday.
Frequently asked questions
How many days are between two dates?
Enter both dates above. The calculator counts every calendar day from the start date up to (but not including) the end date, and adds one if you choose to include the end day.
Does the result include the end date?
By default, no — it measures the gap between the dates. Tick “Include the end day” to count both the start and end day.
How are working days counted?
Working days include Monday to Friday. Public holidays vary by country and are not subtracted.