Difference between two dates in minute, hours javascript

Question

I want to find difference between two dates. I have tried this code but it gives me wrong values. I want get total minutes between two dates, so I am converting hours to minutes and adding to minutes.

var hourDiff = timeEnd - timeStart;
var diffHrs = Math.round((hourDiff % 86400000) / 3600000);
var diffMins = Math.round(((hourDiff % 86400000) % 3600000) / 60000);
diffMins = diffMins + (diffHrs * 60);

Here timeEnd is Mon Jan 01 2007 11:30:00 GMT+0530 (India Standard Time),

and timeStart is Mon Jan 01 2007 11:00:00 GMT+0530 (India Standard Time).

Here if hours difference I am getting 1, it should be 0 and minutes I am getting 30 that is right. But hours should be 0. Am I doing something wrong here?

Answer 1

Try this code (uses ms as initial units)

var timeStart = new Date("Mon Jan 01 2007 11:00:00 GMT+0530").getTime();
var timeEnd = new Date("Mon Jan 01 2007 11:30:00 GMT+0530").getTime();
var hourDiff = timeEnd - timeStart; //in ms
var secDiff = hourDiff / 1000; //in s
var minDiff = hourDiff / 60 / 1000; //in minutes
var hDiff = hourDiff / 3600 / 1000; //in hours
var humanReadable = {};
humanReadable.hours = Math.floor(hDiff);
humanReadable.minutes = minDiff - 60 * humanReadable.hours;
console.log(humanReadable); //{hours: 0, minutes: 30}

JSFiddle: http://jsfiddle.net/n2WgW/

Answer 2

Try:

var diffHrs = Math.floor((hourDiff % 86400000) / 3600000);

Math.round rounded the 0.5 hour difference up to 1. You only want to get the "full" hours in your hours variable, do you remove all the minutes from the variable with the Math.floor()