Subtract days from a date in JavaScript

Question

Does anybody know of an easy way of taking a date (e.g. Today) and going back X days?

So, for example, if I want to calculate the date 5 days before today.

Answer 1

If you want to both subtract a number of days and format your date in a human readable format, you should consider creating a custom DateHelper object that looks something like this :

var DateHelper = {
    addDays : function(aDate, numberOfDays) {
        aDate.setDate(aDate.getDate() + numberOfDays); // Add numberOfDays
        return aDate;                                  // Return the date
    },
    format : function format(date) {
        return [
           ("0" + date.getDate()).slice(-2),           // Get day and pad it with zeroes
           ("0" + (date.getMonth()+1)).slice(-2),      // Get month and pad it with zeroes
           date.getFullYear()                          // Get full year
        ].join('/');                                   // Glue the pieces together
    }
}

// With this helper, you can now just use one line of readable code to :
// ---------------------------------------------------------------------
// 1. Get the current date
// 2. Subtract 5 days
// 3. Format it
// 4. Output it
// ---------------------------------------------------------------------
document.body.innerHTML = DateHelper.format(DateHelper.addDays(new Date(), -5));

(see also this Fiddle)

Answer 2

I like the following because it is one line. Not perfect with DST changes but usually good enough for my needs.

var fiveDaysAgo = new Date(new Date() - (1000*60*60*24*5));

Answer 3

I converted into millisecond and deducted days else month and year won't change and logical

var numberOfDays = 10;//number of days need to deducted or added
var date = "01-01-2018"// date need to change
var dt = new Date(parseInt(date.substring(6), 10),        // Year
              parseInt(date.substring(3,5), 10) - 1, // Month (0-11)
              parseInt(date.substring(0,2), 10));
var new_dt = dt.setMilliseconds(dt.getMilliseconds() - numberOfDays*24*60*60*1000);
new_dt = new Date(new_dt);
var changed_date = new_dt.getDate()+"-"+(new_dt.getMonth()+1)+"-"+new_dt.getFullYear();

Hope helps

Answer 4

A few of the existing solutions were close, but not quite exactly what I wanted. This function works with both positive or negative values and handles boundary cases.

function addDays(date, days) {
    return new Date(
        date.getFullYear(),
        date.getMonth(),
        date.getDate() + days,
        date.getHours(),
        date.getMinutes(),
        date.getSeconds(),
        date.getMilliseconds()
    );
}

Answer 5

Try something like this:

 var d = new Date();
 d.setDate(d.getDate()-5);

Note that this modifies the date object and returns the time value of the updated date.

var d = new Date();

document.write('Today is: ' + d.toLocaleString());

d.setDate(d.getDate() - 5);

document.write('<br>5 days ago was: ' + d.toLocaleString());

Answer 6

When setting the date, the date converts to milliseconds, so you need to convert it back to a date:

This method also take into consideration, new year change etc.

function addDays( date, days ) {
    var dateInMs = date.setDate(date.getDate() - days);
    return new Date(dateInMs);
}

var date_from = new Date();
var date_to = addDays( new Date(), parseInt(days) );