1const date1 = new Date('7/13/2010');
2const date2 = new Date('12/15/2010');
3console.log(getDifferenceInDays(date1, date2));
4console.log(getDifferenceInHours(date1, date2));
5console.log(getDifferenceInMinutes(date1, date2));
6console.log(getDifferenceInSeconds(date1, date2));
7
8function getDifferenceInDays(date1, date2) {
9  const diffInMs = Math.abs(date2 - date1);
10  return diffInMs / (1000 * 60 * 60 * 24);
11}
12
13function getDifferenceInHours(date1, date2) {
14  const diffInMs = Math.abs(date2 - date1);
15  return diffInMs / (1000 * 60 * 60);
16}
17
18function getDifferenceInMinutes(date1, date2) {
19  const diffInMs = Math.abs(date2 - date1);
20  return diffInMs / (1000 * 60);
21}
22
23function getDifferenceInSeconds(date1, date2) {
24  const diffInMs = Math.abs(date2 - date1);
25  return diffInMs / 1000;
26}

1var given = moment("2018-03-10", "YYYY-MM-DD");
2var current = moment().startOf('day');
3
4//Difference in number of days
5moment.duration(given.diff(current)).asDays();

1var a = moment([2007, 0, 29]);
2var b = moment([2007, 0, 28]);
3a.diff(b, 'days') 

1moment(new Date()).diff(moment(new Date()), 'days') // 0

1var now  = "04/09/2013 15:00:00";
2var then = "02/09/2013 14:20:30";
3
4var ms = moment(now,"DD/MM/YYYY HH:mm:ss").diff(moment(then,"DD/MM/YYYY HH:mm:ss"));
5var d = moment.duration(ms);
6var s = d.format("hh:mm:ss");
7
8// outputs: "48:39:30"

1var admission = moment('{date1}', 'DD-MM-YYYY'); 
2var discharge = moment('{date2}', 'DD-MM-YYYY');
3discharge.diff(admission, 'days');