How to use the days between dates calculator
Choose two dates and you are done. We calculate how many days there are between them and also show the result in weeks.
- 1Choose the start date.
- 2Choose the end date.
- 3Press “Calculate difference” to see the result.
Date guide
How many days are there between two dates?
Counting the days between two dates sounds easy. And well... if they are close together, it probably is. The problem starts when you cross several months, February shows up with its 28 or 29 days, or you have one or more years in between. Counting on your fingers is not such a great idea then.
How the calculation works
The idea is simple: we take the two dates and calculate the actual time separating them. If the result is 45 days, it is 45 days. It does not matter whether the period passes through February, a 30-day month, or a 31-day month.
Then we divide that total by seven to show it as complete weeks too. For example, 45 days is 6 weeks and 3 days.
What you can use it for
For anything you need to count between two dates: how long until a trip, how many days a project lasted, how much time has passed since an event, or simply how many days there are between today and a date you have in mind.
You can also use dates from the past. The calculator does not need one of them to be today.
Months and leap years
Here is one of the reasons counting by hand gets annoying: months are not all the same length. Some have 30 days, others 31, and February decided to stick with 28... except when it has 29.
You do not need to correct any of that. The calculator works with real calendar dates, so if there is a February 29 between the two dates, that day is included automatically.
How to read the result
The most direct number is “Total days”. If it says 100, there are 100 days of difference between the two dates.
Weeks simply show the same period another way. For example, 100 days equals 14 complete weeks and 2 days.
What if you entered the dates backwards? No worries. If you select the more recent date first, we reverse the order and show the positive difference. In the end, what you usually want to know is how much time separates one date from the other.
The calculation happens in your browser
Your dates are used in your browser to do the calculation. You do not need an account or to send them to a server. Choose the dates, we calculate, and that is it.
Questions about days between dates
Does the calculator count the start and end dates?
We calculate the days that have passed between the two dates. For example, there is 1 day of difference from May 1 to May 2. If you need to count both days as part of a period—the 1st and the 2nd—that would be 2 days, so add one to the result.
What happens if I enter the dates backwards?
Nothing bad. If you enter the more recent date first, we reverse the order to show a positive difference and let you know in the result.
Does it account for leap years?
Yes. If a February 29 falls between the two dates, it counts like any other day. You do not need to make any adjustment.
Are my dates saved?
No. The calculation happens directly in your browser, and you do not need to send the dates to a calculation server.
If you are calculating a legal, employment, or contractual deadline, be careful: a certain number of days passing does not necessarily mean that is the official way to count the deadline. Rules may apply to business days, holidays, or whether the starting day is included.