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Date Difference Calculator

Calculate the exact difference between two dates in days, weeks, months, and years.

Enter your dates

Include end date Turn this on to count both the start date and end date in the result.

This calculator gives the calendar difference between two dates and also shows the total number of days and weeks.

Total difference
0 days
Select two dates to see the difference.
Total days
0
Total weeks
0
Calendar months
0
Calendar years
0

Date breakdown

Start date —
End date —
Difference 0 years, 0 months, 0 days
Inclusive mode Off

How This Date Difference Calculator Works

This date difference calculator measures the time between two calendar dates and shows the result in several useful ways. You can see the total number of days, total weeks, and a calendar-style breakdown in years, months, and days.

It is useful for planning holidays, checking contract periods, measuring project timelines, working out age spans, and calculating the length of time between milestones or deadlines.

The calculator also includes an optional inclusive setting. When this is turned on, both the start date and the end date are counted in the final result. When it is turned off, the result shows the standard difference between the two dates.

If the dates are entered in reverse order, the calculator automatically reorders them and still gives the correct result.

Total days The full number of days between the two selected dates, useful for countdowns and timelines.
Total weeks A simple week-based version of the same date span, helpful for planning longer periods.
Calendar breakdown The result is also shown as years, months, and days based on real calendar dates.
Inclusive mode You can include both boundary dates when you need to count the full date range.
Back to calculator ↑

Example Date Differences

Holiday countdown
Start date1 June 2026
End date15 June 2026
Total difference14 days
Calendar breakdown = 0 years, 0 months, 14 days
Project timeline
Start date10 January 2026
End date10 April 2026
Total difference90 days
Calendar breakdown = 0 years, 3 months, 0 days
Birthday age span
Start date5 March 2000
End date5 March 2026
Total difference9,496 days
Calendar breakdown = 26 years, 0 months, 0 days
Inclusive event count
Start date1 August 2026
End date7 August 2026
Inclusive modeOn
Total difference = 7 days

Date Difference Calculator FAQs

It calculates the time between two dates and shows the result as total days, total weeks, and a calendar breakdown in years, months, and days.
When inclusive mode is turned on, both the start date and the end date are counted in the final total. This is useful for event schedules, bookings, and date ranges where both days should be included.
The calculator automatically swaps the dates and still gives you the correct difference, so you do not need to re-enter them.
Months do not all contain the same number of days, so a result shown as calendar months and days will not always match a fixed number of days per month. Both formats are correct and useful for different situations.
Yes. The calculator uses real calendar dates, so leap years and varying month lengths are included automatically.
It is accurate for standard calendar date calculations and is designed for everyday use such as planning, countdowns, timelines, date checks, and age spans.

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