Compute elapsed time [duplicate]

Try something like this (FIDDLE)

// record start time
var startTime = new Date();

...

// later record end time
var endTime = new Date();

// time difference in ms
var timeDiff = endTime - startTime;

// strip the ms
timeDiff /= 1000;

// get seconds (Original had 'round' which incorrectly counts 0:28, 0:29, 1:30 ... 1:59, 1:0)
var seconds = Math.round(timeDiff % 60);

// remove seconds from the date
timeDiff = Math.floor(timeDiff / 60);

// get minutes
var minutes = Math.round(timeDiff % 60);

// remove minutes from the date
timeDiff = Math.floor(timeDiff / 60);

// get hours
var hours = Math.round(timeDiff % 24);

// remove hours from the date
timeDiff = Math.floor(timeDiff / 24);

// the rest of timeDiff is number of days
var days = timeDiff ;