Date & Time Calculators
Date Difference Calculator
Find the exact number of days, weeks and months between any two dates, with a handy option to swap them.
About the Date Difference Calculator
The date difference calculator tells you exactly how much time separates two dates. It is perfect for counting the days between two events, measuring project durations, or working out how long ago something happened.
Enter a start and end date and the tool reports the total days, weeks and months, plus a precise breakdown in years, months and days.
How to use the Date Difference Calculator
- Choose the start date and end date.
- Click Calculate Difference.
- If you entered them the wrong way round, use Swap dates.
- Review the totals and the year/month/day breakdown.
How the calculation works
Difference (days) = End Date − Start Date
The calculator also expresses the gap in complete years, months and remaining days for a human-friendly reading.
Example
From 1 January 2026 to 31 December 2026 there are 364 days — about 52 weeks, or 11 months and 30 days.
Frequently asked questions
Enter both dates and the calculator subtracts one from the other to give the exact number of days between them.
It counts the number of days from the start date up to the end date; add one if you need both endpoints included.
Yes. If the end date is earlier, the tool automatically uses the absolute difference, or you can swap them.
Yes, it accounts for different month lengths so the years-months-days figure is accurate.