ES6 - getDay() Method
JavasScript date getDay() method returns the day of the week for the specified date according to local time. The value returned by getDay is an integer corresponding to the day of the week: 0 for Sunday, 1 for Monday, 2 for Tuesday, and so on.
Returns the day of the week for the specified date according to local time.
var dt = new Date("December 25, 1995 23:15:00"); console.log("getDay() : " + dt.getDay() );
getDay() : 1