How to calculate number of days between two dates

How to calculate number of days between two dates

I have two input dates taking from Date Picker control. I have selected start date 2/2/2012 and end date 2/7/2012. I have written following code for that.
I should get result as 6 but I am getting 5.
function SetDays(invoker) {
var start = $find(‘<%=StartWebDatePicker.ClientID%>‘).get_value();
var end = $find(‘<%=EndWebDatePicker.ClientID%>‘).get_value();

var oneDay=1000 * 60 * 60 * 24;
var difference_ms = Math.abs(end.getTime() – start.getTime())
var diffValue = Math.round(difference_ms / oneDay);

Can anyone tell me how I can get exact difference?


Solution 1: or

From Moment docs:

var a = moment([2007, 0, 29]);
var b = moment([2007, 0, 28]);
a.diff(b, 'days')   // =1

or to include the start:

a.diff(b, 'days')+1   // =2

Beats messing with timestamps and time zones manually.

Depending on your specific use case, you can either

  1. Use a/b.startOf('day') and/or a/b.endOf('day') to force the diff to be inclusive or exclusive at the “ends” (as suggested by @kotpal in the comments).
  2. Set third argument true to get a floating point diff which you can then Math.floor, Math.ceil or Math.round as needed.
  3. Option 2 can also be accomplished by getting 'seconds' instead of 'days' and then dividing by 24*60*60.

Solution 2:

If you are using moment.js you can do it easily.

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var start = moment("2018-03-10", "YYYY-MM-DD");
var end = moment("2018-03-15", "YYYY-MM-DD");

//Difference in number of days

//Difference in number of weeks

If you want to find difference between a given date and current date in number of days (ignoring time), make sure to remove time from moment object of current date as below


To find difference between a given date and current date in number of days

var given = moment("2018-03-10", "YYYY-MM-DD");
var current = moment().startOf('day');

//Difference in number of days

Solution 3:


//Difference in days

var diff =  Math.floor(( start - end ) / 86400000);

Solution 4:

Try this Using moment.js (Its quite easy to compute date operations in javascript)

firstDate.diff(secondDate, ‘days’, false);// true|false for fraction value

Result will give you number of days in integer.

Solution 5:

Also you can use this code: moment(“yourDateHere”, “YYYY-MM-DD”).fromNow(). This will calculate the difference between today and your provided date.