Moment.js moment().weeksInYear() Method

The moment().weeksInYear() method is used to return the number of weeks in the current year of the Moment object. This method is locale specific, hence the number might vary depending on the current locale of the Moment.

Syntax:

moment().weeksInYear();

Parameters: This method does not accept any parameters.

Return Value: This method returns the number of weeks in the current year of the Moment object.

Note: This will not work in the normal Node.js program because it requires an external moment.js library to be installed globally or in the project directory.

Moment.js can be installed using the following command:

Installation of moment module:

npm install moment

The below examples will demonstrate the Moment.js moment().weeksInYear() Method.

Example 1:

Javascript

const moment = require('moment');

console.log("Current Date:", moment().toString())
console.log("Current year is:", moment().year())

let year2050 = moment().year(2050);
console.log(
    "Weeks in Year 2050 is:",
    year2050.weeksInYear()
)

let year1950 = moment().year(1950);
console.log(
    "Weeks in Year 1950 is:",
    year1950.weeksInYear()
)

Output:

Current Date: Mon Jul 11 2022 02:14:41 GMT+0530
Current year is: 2022
Weeks in Year 2050 is: 53
Weeks in Year 1950 is: 52

Example 2:

Javascript

const moment = require('moment');

console.log("Current Date:", moment().toString())
console.log("Current year is:", moment().year())

for (let i = 2000; i < 2030; i++) {
    console.log(
        `Weeks in Year ${i} is: ${moment().year(i).weeksInYear()}`
    )
}

Output:

Weeks in Year 2000 is: 53
Weeks in Year 2001 is: 52
Weeks in Year 2002 is: 52
Weeks in Year 2003 is: 52
Weeks in Year 2004 is: 52
Weeks in Year 2005 is: 53
Weeks in Year 2006 is: 52
Weeks in Year 2007 is: 52
Weeks in Year 2008 is: 52
Weeks in Year 2009 is: 52
Weeks in Year 2010 is: 52
Weeks in Year 2011 is: 53
Weeks in Year 2012 is: 52
Weeks in Year 2013 is: 52
Weeks in Year 2014 is: 52
Weeks in Year 2015 is: 52
Weeks in Year 2016 is: 53
Weeks in Year 2017 is: 52
Weeks in Year 2018 is: 52
Weeks in Year 2019 is: 52
Weeks in Year 2020 is: 52
Weeks in Year 2021 is: 52
Weeks in Year 2022 is: 53
Weeks in Year 2023 is: 52
Weeks in Year 2024 is: 52
Weeks in Year 2025 is: 52
Weeks in Year 2026 is: 52
Weeks in Year 2027 is: 52
Weeks in Year 2028 is: 53
Weeks in Year 2029 is: 52

Reference: https://momentjs.com/docs/#/get-set/weeks-in-year/