Get first and last date of current month with javascript or jquery - Stack Overflow

Very simple, no library required:

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

or you might prefer:

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

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