How do I subtract minutes from a date in JavaScript?

Question

Once you know this:

• You can create a Date by calling the constructor with milliseconds since Jan 1, 1970.
• The valueOf() a Date is the number of milliseconds since Jan 1, 1970
• There are 60,000 milliseconds in a minute :-]

In the code below, a new Date is created by subtracting the appropriate number of milliseconds from myEndDateTime:

var MS_PER_MINUTE = 60000;
var myStartDate = new Date(myEndDateTime - durationInMinutes * MS_PER_MINUTE);

You can also use get and set minutes to achieve it:

var endDate = somedate;

var startdate = new Date(endDate);

var durationInMinutes = 20;

startdate.setMinutes(endDate.getMinutes() - durationInMinutes);

Everything is just ticks, no need to memorize methods...

var aMinuteAgo = new Date( Date.now() - 1000 * 60 );

or

var aMinuteLess = new Date( someDate.getTime() - 1000 * 60 );

update

After working with momentjs, I have to say this is an amazing library you should check out. It is true that ticks work in many cases making your code very tiny and you should try to make your code as small as possible for what you need to do. But for anything complicated, use momentjs.

moment.js has some really nice convenience methods to manipulate date objects

The .subtract method, allows you to subtract a certain amount of time units from a date, by providing the amount and a timeunit string.

var now = new Date();
// Sun Jan 22 2017 17:12:18 GMT+0200 ...
var olderDate = moment(now).subtract(3, 'minutes').toDate();
// Sun Jan 22 2017 17:09:18 GMT+0200 ...

Luxon also has an API to manipulate it's own DateTime object

var dt = DateTime.now(); 
// "1982-05-25T00:00:00.000Z"
dt.minus({ minutes: 3 });
dt.toISO();              
// "1982-05-24T23:57:00.000Z"

This is what I found:

//First, start with a particular time
var date = new Date();

//Add two hours
var dd = date.setHours(date.getHours() + 2);

//Go back 3 days
var dd = date.setDate(date.getDate() - 3);

//One minute ago...
var dd = date.setMinutes(date.getMinutes() - 1);

//Display the date:
var monthNames = ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"];
var date = new Date(dd);
var day = date.getDate();
var monthIndex = date.getMonth();
var year = date.getFullYear();
var displayDate = monthNames[monthIndex] + ' ' + day + ', ' + year;
alert('Date is now: ' + displayDate);

Sources:

http://www.javascriptcookbook.com/article/Perform-date-manipulations-based-on-adding-or-subtracting-time/

https://stackoverflow.com/a/12798270/1873386