Need to know how many days, weeks or months are between two dates? Our Date Difference Calculator makes it quick and easy to calculate the exact difference between any two dates.

Simply enter your start date and end date and the calculator will show the total number of days, complete weeks and remaining days, as well as the difference in calendar months and days.

Whether you're calculating the length of a project, counting down to an event, checking a deadline or simply working out how much time has passed, this calculator gives you the answer instantly.

How to Calculate the Difference Between Two Dates

Working out the number of days between two dates is easy when the dates are close together, but it can become more complicated when they span different months or years.

Our Date Difference Calculator works out the elapsed time between two dates and presents the result in several useful ways, including total days, weeks and days, and calendar months and days.

How to use the calculator

1. Enter the start date – Select the date you want your calculation to begin.
   
2. Enter the end date – Select the date you want your calculation to finish.
   
3. Select Calculate Difference – The calculator will work out the time between the two dates.
   
4. View your results – The result will show the total days, weeks and days, and calendar months and days.

You can enter the dates in either order. The calculator will work out the difference between them regardless of which date is entered first.

How are the days calculated?

The calculator calculates the actual number of complete days between the two dates.

For example, if the dates are one week apart, the result will be 7 days, or 1 week and 0 days.

The calculation accounts for different month lengths and leap years, so you don't need to work anything out manually.

How are weeks calculated?

The total number of days is divided into complete seven-day weeks, with any remaining days shown separately.

For example, 17 days would be shown as:

2 weeks and 3 days

This gives you both the total number of days and a more familiar weeks-and-days format.

How are months calculated?

Calendar months are calculated based on the actual dates rather than assuming that every month contains the same number of days.

For example, the period from 15 January to 15 February is 1 calendar month.

The period from 15 January to 20 February is 1 month and 5 days.

This makes the month calculation more useful for periods involving appointments, projects, contracts, subscriptions and other dates where calendar months matter.

What about dates spanning several years?

The calculator can calculate differences between dates that span multiple years.

For example, you can use it to work out the length of a long-term project, the time until a future event or the amount of time that has passed since a particular date.

Leap years and different month lengths are taken into account when calculating the total number of days.

When might you use a Date Difference Calculator?

A date difference calculator can be useful for:

• Calculating the length of a project
• Working out how many days remain until an event
• Calculating the time between appointments
• Checking contract or subscription periods
• Calculating notice periods
• Working out how long something has been running
• Calculating weeks between dates
• Calculating months between dates
• Checking deadlines and important dates
• Planning holidays, events or other activities

Date Difference Calculator vs Time Duration Calculator

These two calculators deal with different types of calculations.

A Date Difference Calculator works with calendar dates, such as 10 September to 25 September.

A Time Duration Calculator works with times during a day, such as 9:00 AM to 5:00 PM.

If you need to calculate the number of days, weeks or months between two dates, use the Date Difference Calculator.

If you need to calculate the hours and minutes between two times, use the Time Duration Calculator.

Important to remember

This calculator calculates the elapsed difference between two calendar dates. The starting date is not counted as a complete elapsed day.

For example, the difference between 1 June and 2 June is 1 day.

If you need to count both the start date and end date as included days, such as for certain booking, leave or event calculations, you may need to add one day to the result.