Answers for "how to get first and last day in the month js"

javascript date first day of current month

var date = new Date();
var firstDay = new Date(date.getFullYear(), date.getMonth(), 1);
var lastDay = new Date(date.getFullYear(), date.getMonth() + 1, 0);

js get first and last day of previous month

var d = new Date();
d.setDate(0); //sets d to the last day of the previous month
d.setDate(1); //sets d the the first day of that month
d.setHours(0,0,0,0); //sets d time to midnight

//d now equals the first day of the month before today