Get week of the month

Question

How can i get the week number of month using javascript / jquery?

For ex.:

First Week: 5th July, 2010. / Week Number = First monday

Answer 1

week_number = 0 | new Date().getDate() / 7

Answer 2

Having struggle with this topic too - thanks to Olson.dev! I've shortened his function a little bit, if somebody is interessted:

// returns week of the month starting with 0
Date.prototype.getWeekOfMonth = function() {
  var firstWeekday = new Date(this.getFullYear(), this.getMonth(), 1).getDay();
  var offsetDate = this.getDate() + firstWeekday - 1;
  return Math.floor(offsetDate / 7);
}

update: if you need a localized version - you have to tweak the firstWeekday variable

// german version - week starts with monday
Date.prototype.getWeekOfMonth = function() {
  var firstWeekday = new Date(this.getFullYear(), this.getMonth(), 1).getDay() - 1;
  if (firstWeekday < 0) firstWeekday = 6;
  var offsetDate = this.getDate() + firstWeekday - 1;
  return Math.floor(offsetDate / 7);
}

Answer 3

Please try below function.This one is considering week start date as Monday and week end date as Sunday.

getWeekNumber(date) {
    var monthStartDate =new Date(new Date().getFullYear(), new 
         Date().getMonth(), 1);
    monthStartDate = new Date(monthStartDate);
    var day = startdate.getDay();
    date = new Date(date);
    var date = date.getDate();
    return Math.ceil((date+ day-1)/ 7);
}

Answer 4

This is a few years on, but I've needed to use this functionality recently and, for certain dates in years 2016/2020 (such as January 31st), none of the code here works.

It's not the most efficient by any means, but hopefully this helps someone out as it's the only thing I could get working for those years along with every other year.

Date.prototype.getWeekOfMonth = function () {
    var dayOfMonth = this.getDay();
    var month = this.getMonth();
    var year = this.getFullYear();
    var checkDate = new Date(year, month, this.getDate());
    var checkDateTime = checkDate.getTime();
    var currentWeek = 0;

    for (var i = 1; i < 32; i++) {
        var loopDate = new Date(year, month, i);

        if (loopDate.getDay() == dayOfMonth) {
            currentWeek++;
        }

        if (loopDate.getTime() == checkDateTime) {
            return currentWeek;
        }
    }
};

Answer 5

function getWeekOfMonth(date) {
  const startWeekDayIndex = 1; // 1 MonthDay 0 Sundays
  const firstDate = new Date(date.getFullYear(), date.getMonth(), 1);
  const firstDay = firstDate.getDay();

  let weekNumber = Math.ceil((date.getDate() + firstDay) / 7);
  if (startWeekDayIndex === 1) {
    if (date.getDay() === 0 && date.getDate() > 1) {
      weekNumber -= 1;
    }

    if (firstDate.getDate() === 1 && firstDay === 0 && date.getDate() > 1) {
      weekNumber += 1;
    }
  }
  return weekNumber;
}

I hope this works Tested until 2025

Answer 6

function getWeekOfMonth(date) {

  var nth = 0; // returning variable.
  var timestamp = date.getTime(); // get UTC timestamp of date.
  var month = date.getMonth(); // get current month.
  var m = month; // save temp value of month.

  while( m == month ) {  // check if m equals our date's month.
    nth++; // increment our week count.
    // update m to reflect previous week (previous to last value of m).
    m = new Date(timestamp - nth * 604800000).getMonth();
  }

  return nth;

}