JavaScript’s built-in support for date handling is useful, but it can be awkward to use. Complex operations like timezone conversions and date formatting are often challenging.

Luckily, several packages are available that make working with dates and times in JavaScript less stressful. Here, you will learn about some of these packages and how you can get started working on these packages.

1. Moment.js

When it comes to working with dates and times, the native JavaScript Date object has limited functionality.

Moment.js, a JavaScript library, introduced many features unavailable in the native Date object. As a result, it’s become the go-to library for working with dates and times.

To install Moment.js with npm, run the following command from your project directory: 

        npm install moment

After installation, you can import Moment.js into your project and perform operations with the library: 

        const moment = require('moment');
const now = moment();
const nowString = now.format('YYYY-MM-DD HH:mm:ss');

console.log(`The current date and time is ${nowString}`);

This code snippet imports the Moment.js library and creates a moment object using the current date and time with the moment() function. It then demonstrates how to format the created date object as a string with the format() method, which takes a date/time format as its argument.

You can also use this library to add and subtract time intervals: 

        const addTenMinutes = moment().add(10, 'minutes');
console.log(`${addTenMinutes.format('h:mm a')}`);

const subtractTwoDays = moment().subtract(2, 'days');
console.log(`${subtractTwoDays.format('dddd, MMMM Do YYYY')}`);

The program logs two variables to the console, in different formats. The first, addTenMinutes, holds the result of adding 10 minutes to the current date and time. The second, subtractTwoDays, has the current date and time value with two days subtracted from it.

Moment.js can perform other operations like checking for leap years and converting from one date format to another.

It is important to note that Moment.js is no longer maintained by its core developer team. The developers advise using an alternative like Luxon.js.

2. Luxon.js

Luxon.js is a robust and more modern JavaScript library for working with dates. An alternative to Moment.js, it addresses limitations of the older library like mutability.

You can install Luxon with npm and then import its DateTime class in your Node.js project using the require() function: 

        const { DateTime } = require('luxon');

In Luxon, DateTime objects refer to time instances that go all the way down to milliseconds.

You can create new DateTime objects and access their components, like the year, month, minute, and second: 

        const now = DateTime.now();
const year = now.year;
const minute = now.minute;
const second = now.second;

This code creates a new DateTime object representing the current date and time using the now() method. It then accesses that date’s components using the year, minute, and second properties.

A major difference between Luxon.js and Moment.js is its immutable character. All DateTime objects are immutable in Luxon, meaning that you cannot modify DateTime properties. Instead, you can create new DateTime instances from existing ones.

For example: 

        const now = DateTime.now();
const tomorrow = now.plus({ days: 1 });

This code creates a new DateTime object named tomorrow based on the now object, using the plus method, passing it a value of 1 day as an argument. The plus method creates a new DateTime object with the specified number of days added to the original object.

Another advantage of Luxon.js is its reliable timezone support, which is essential for working with dates and times in modern web applications. The library uses the Internationalization API in modern browsers to provide accurate timezone support.

However, one of the downsides of Luxon.js is its limited community resources.

3. Date-fns

Date-fns is a very lightweight JavaScript library designed for working with dates and times. It builds on the native JavaScript Object.

Date-fns uses functional programming techniques and incorporates an immutable feature, which makes working with dates simpler and reduces the likelihood of bugs in your code.

After installing date-fns with npm, import the package into your program using the require function: 

        const { format, addDays } = require('date-fns');

Date-fns is modular. It contains a lot of functions that you can access by destructuring the package, as shown in the code block above. The code imports only the format and addDays functions from the date-fns library.

Here is an example of how to use both those functions: 

        const today = new Date();
const formattedDate = format(today, 'yyyy-MM-dd');
console.log(formattedDate); 

const tomorrow = format(addDays(today, 1), 'yyyy-MM-dd');
console.log(tomorrow);

This program demonstrates using the date-fns library in JavaScript to format and manipulate dates.

It creates a new Date object representing the current date. It formats the current date using the format function from the date-fns library.

It then uses the addDays function to create a new Date object representing tomorrow's date, formats it using the format function, and logs both the current date and tomorrow's date to the console in "yyyy-MM-dd" format.

A downside to using Date-fns is that it doesn't provide timezone support. Instead, it uses a separate library to work with time zones using helper functions.

4. Day.js

Day.js, another very lightweight library, is a good choice if you’re looking for an immutable, smaller, faster alternative to Moment.js.

You can install Day.js as a package in your JavaScript project by running the following npm command: 

        npm install dayjs

To import Day.js into your project after installation, you can use the following code: 

        const dayjs = require('dayjs')

Here are some basic functions and methods available in Day.js 

        const now = dayjs();

const date = dayjs('2023-03-23', 'YYYY-MM-DD');

const month = date.month();

const formattedDate = date.format('MMMM D, YYYY');

const nextWeek = date.add(1, 'week');

The above code creates a new Day.js object representing the current date and time, parses a date string with a custom format, and gets the month from the date variable. It also shows how to format and add to a date instance.

Like Date-fns, Day.js can not provide time zone support on its own. Day.js uses a plugin system, making it confusing to use.

Of the packages covered, Day.js is the most similar to Moment.js. This makes it easier to switch between the two if you need to.

Choosing the Right Library for Your App

Choosing the right date and time library for your JavaScript application is an important decision that can have a big impact on the quality and maintainability of your code.

Each of the libraries discussed here has its strengths and weaknesses, so it's important to carefully evaluate your requirements before making a decision.