Date Difference Calculator
Count the exact days, weeks, months, and years between any two dates
Date Difference Calculator
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Frequently Asked Questions
How many days between two dates?
Enter both dates and our calculator instantly shows the difference in days, weeks, months, and years.
Does the calculator count weekends?
Yes, by default all calendar days are counted. You can toggle to count only weekdays (Monday–Friday).
What is the difference between a calendar month and 30 days?
Calendar months vary from 28 to 31 days. For precise calculations, we count exact days then convert.
About this calculator
Date Difference Calculator counts the days, weeks, months and years between any two dates. It can include or exclude weekends, and it gives you the answer in the units people use for planning: total days, whole weeks and approximate months.
Typical uses: how long until a deadline, how many days a project took, the length of a notice period, or the gap between two events. Both dates are included in the count only if you choose to include them, so you can match whichever convention your contract uses.
How to use it
- Pick the Start Date and the End Date.
- Tick or untick weekdays only depending on whether you want business days.
- Press Calculate Difference.
- Read the days, weeks, months and years.
Calculation
Days = End − Start in calendar days. Weeks = Days ÷ 7, Months ≈ Days ÷ 30.44 and Years ≈ Days ÷ 365.25. The weekday count removes Saturdays and Sundays from the total.
Worked example
1 January 2026 to 31 December 2026
| Days between | 364 |
| Weeks | 52 |
| Months | about 11 |
Counting both dates would make it 365 days. State which convention you are using in any agreement.
Tips and common mistakes
- Check whether the end date counts. Legal notice periods often count it, deadlines often do not.
- Weekday counts do not remove public holidays.
- Months and years in the result are approximations because months differ in length.
- Use the Date Calculator when you need to add a number of days to a date.
- The order of the dates does not matter.
Frequently asked questions
How many days are there between two dates?
Subtract the earlier date from the later one. The tool does it for you and shows weeks and months as well.
Does the calculation include the end date?
No. It counts the days from the start up to, but not including, the end date.
Can I exclude weekends?
Yes, use the weekdays option.
Are public holidays removed?
No. Subtract them yourself after checking your calendar.
How many weeks are in a year?
52 weeks and one day, or two in a leap year.
What if the end date is before the start?
The tool uses the absolute difference.