Comparing Javascript & jQuery Through Building a Pomodoro Timer

Modern web development offers an incredible variety of tools, libraries, and frameworks to build web sites/applications. As of 2016, jQuery, React, Angular, and Vue are the most popular front-end libraries/frameworks in use. They can all be used to build and accomplish similar things, but in different ways. What are the advantages/disadvantages of each? How does each approach vary? What do the new tools of React, Vue, and Angular 2 offer that Angular 1, JavaScript, and vanilla JS didn’t?

In this 3 part tutorial series, we’re going to build a simple pomodoro timer as a means to compare vanilla JavaScript, jQuery, React, Angular 1, Angular 2 and Vue.

What is a pomodoro timer?

The pomodoro timer is an easy-to-use productivity method. Using this method, you work in 25 minute spurts with 5 minute breaks in between. Many people find it helpful for helping them focus and work on tasks during the day.


Project Overview

In this tutorial, first we will create a pomodoro timer using vanilla javascript. Then, we will re-create the same pomodoro timer using jQuery.

Here is how the final version of pomodoro timer built using vanilla javascript looks like :

See the Pen Pomodoro Timer : : Javascript by Raj Gupta (@rajdgreat007) on CodePen.

Here is how the final version of pomodoro timer built using jQuery looks like :

See the Pen Pomodoro Timer : : jQuery by Raj Gupta (@rajdgreat007) on CodePen.

Our pomodoro timer shows minutes, seconds, and gives simple control buttons. It’s a simple timer but can give enormous productivity gains if used right.

Building the Pomodoro Timer : Javascript

Let’s first write the html code to create various elements of the pomodoro timer.

As you can see, nothing fancy here. Just a container with the timer and control buttons. We will be using a background filler that will keep increasing as time progresses.

Let’s apply some css to the above markup to make it look nice.

Now the timer looks nice, but there is no functionality associated with it yet. Let’s add javascript to make it functional.

We will be using object oriented javascript in which all of the variables and functions of the pomodoro timer will be encapsulated inside an object. Below is the basic structure of the code :

Building the  Pomodoro Timer : jQuery

Now we’re going to build this exact same app in jQuery. The HTML and CSS are exactly same as that of above.

First of all, I would like to mention that jQuery is a huge library. In our pomodoro app, we have used a very small subset of the features that it offers. This is the biggest disadvantage of using jQuery for our case because we will be loading entire library and because of that, the page load time will be much higher as compared to javascript’s pomodoro app. In huge pages, using jQuery makes a lot of sense.

In the above code we are using $(‘#minutes’) for caching the minutes DOM element.  As a matter of fact, javascript’s document.querySelector(‘#minutes’) is way faster than jQuery’s $(‘#minutes’). This speed difference could not be realised in a small app (such as a pomodoro timer) but it is relevant for large pages where there is intensive DOM query. Javascript’s document.getElementById(‘minutes’) is even faster than document.querySelector(‘#minutes’). So, the speed of executions has the following order :

document.getElementById(‘minutes’)  > document.querySelector(‘#minutes’) > $(‘#minutes’)

The reason for the above speed difference being, under the hood $(‘#minutes’) boils down to document.getElementById(‘minutes’) wrapped by jQuery wrapper. But when we say $(‘#minutes’), jQuery has to a lot of work in identifying if the argument is a string, does it contain spaces, it starts with a ‘.’ or a ‘#’ or is it a tagname and so on. This extra work takes time and hence reduces the speed.

Although, jQuery is at disadvantage because its DOM query speed is less as compared to javascript but when it comes to code convenience, jQuery is far ahead of javascript.

In the pomodoro app created using javascript, we can easily spot long lines of code whereas in the app created using jquery, the code seems relatively short. That means, if we are using jQuery, we have to type less as compared to javascript to achieve the same functionality. Whereas in javascript there are different methods to query DOM (by id, class and tagname), in jQuery, one single selector takes care of all of them.

Moreover,  javascript’s document.querySelector(‘#work’) will not work in all the browsers. It may break in IE8. On the other hand, jQuery’s $(‘#work’) is guaranteed to work in all the browsers. The reason is, all jQuery’s methods are standardised to work across all browsers.

Additionally, jQuery provides support for chaining which means that we can chain a method call at the end of another method call and save few bytes by saving the amount of code required to be written if chaining was not supported. For example, we can do the following in jQuery :

Here we have chained show() method at the end of css() method. On the other hand, javascript doesn’t support method chaining.

In jQuery, we are using $(document).ready(), to make sure that DOM is ready before we query it. In javascript, we used window.onload event to achieve the same. jQuery’s $(document).ready() event occurs earlier as compared to window.onload of javascript because the latter occurs after the DOM is loaded and all the resources (scripts, images etc) are also loaded.

Last but not the least, while writing javascript code, there is big scope for writing inefficient code. jQuery library on the other hand, is tested over time and highly optimised. Thus, if used carefully, the scope for writing inefficient code using jQery is very less as compared to javascript.


We created two pomodoro apps, one using vanilla javascript and other using jQuery. The two approaches are fairly similar, but jQuery offers an easier syntax in querying for elements and offers shorter (albeit slower) ways of doing things compared to JavaScript.

The differences between libraries/frameworks will get much more interesting in future posts, where we use Angular, React, and Vue to build this same app.

Muhammad Uzair khalid
Independent Author and Coder.