Loop through a date range with JavaScript

Tom Gullen picture Tom Gullen · Dec 3, 2010 · Viewed 131.2k times · Source

Given two Date() objects, where one is less than the other, how do I loop every day between the dates?

for(loopDate = startDate; loopDate < endDate; loopDate += 1)
{

}

Would this sort of loop work? But how can I add one day to the loop counter?

Thanks!

Answer

David Johnstone picture David Johnstone · Apr 6, 2012

Here's a way to do it by making use of the way adding one day causes the date to roll over to the next month if necessary, and without messing around with milliseconds. Daylight savings aren't an issue either.

var now = new Date();
var daysOfYear = [];
for (var d = new Date(2012, 0, 1); d <= now; d.setDate(d.getDate() + 1)) {
    daysOfYear.push(new Date(d));
}

Note that if you want to store the date, you'll need to make a new one (as above with new Date(d)), or else you'll end up with every stored date being the final value of d in the loop.