Best Practices for Optimizing Frontend Performance
Tags: frontend, javascript, programming, webdev
Published: 2023-03-17 03:12:23

Optimizing web performance from the frontend is essential because it can have a significant impact on the user experience of a website. The frontend of a website consists of the code that runs in the user's web browser and is responsible for displaying the content and functionality of the website. If the frontend code is inefficient or poorly optimized, it can result in slow page load times, unresponsive user interfaces, and other performance issues.

The main reason to optimize web performance from the frontend is:

1. Faster page load times: When a website loads quickly, it can improve the user experience and reduce bounce rates(bounce rates means the percentage of visitors to a particular website who navigate away from the site after viewing only one page). Optimizing frontend code can reduce the amount of time it takes for a website to load.
2. Better user engagement: A website that responds quickly and smoothly to user interactions can improve user engagement and increase the time spent on the site.

So, in this article, I will discuss best practices that can be used to optimize the frontend performance-

1. **Minification of resources:** It refers to the process of removing unnecessary, redundant data from your HTML, CSS, and JavaScript that are not required to load. This includes eliminating code comments and formatting, white space characters, unused codes, newline characters, and so on. Minification of HTML, CSS, and JavaScript will speeds up the frontend load times as it reduces the amount of code that needs to be requested from the server.

2. **Reduce the Number of Server Calls:** It is a crucial technique used to optimize web performance from the frontend. A server call occurs when the user's browser requests data from the server, such as images, stylesheets, or JavaScript files. Each server call adds additional overhead to the page load time and can impact the user experience.

3. **Optimizing images:** It is a crucial technique used to optimize web performance from the frontend. Images can be a significant contributor to the size of a web page, and larger image sizes can lead to slower page load times, which can negatively impact the user experience.
Using SVG (Scalable Vector Graphics) images is a popular technique used to optimize web performance from the frontend.
Here are some reasons why using SVG images can be beneficial for optimizing web performance:

       (a) **Smaller file size:** Compared to images, such as JPEG or PNG, SVG images have a significantly smaller file size.

       (b) **Scalability:** SVG images are highly scalable and can be resized without losing quality. This means that you can use the same image on multiple devices, such as desktops, tablets, and smartphones, without having to create different versions of the image.

      (c) **Faster loading times:** Because SVG images have a smaller file size, they can be loaded more quickly than larger images such as JPEG or PNG, resulting in faster page load times.

      Also using new image formats like **WebP** and **AVIF** gives a better performance than older formats like **JPEG** and **PNG**. **WebP** is 26% smaller compared to **PNG** and 25–35% smaller compared to **JPEG**. **AVIF** is 50% smaller compared to **JPEG** and 20% smaller compared to **WebP**. However, the downside is with the browser support. **WebP** gained browser support recently, so older versions might not support it. On the other hand, **AVIF** is only supported in Chrome and Opera.
4. **Apply Lazy Loading:** It helps to improve frontend loading time. With lazy loading, the web page loads only the required content first and loads the remaining content when the user needs it. Lazy loading is a technique that is widely used in real-world scenarios to improve web performance. Here are some examples of how lazy loading is implemented in different scenarios:
    (a) **Image-heavy websites:** Websites that rely heavily on images, such as online stores or photography websites, can benefit greatly from lazy loading. In this scenario, images are loaded only when they are in the user's viewport, allowing the website to load faster and reducing the amount of data that needs to be transferred.

    (b) **Infinite scroll:** Websites that implement infinite scroll, such as social media platforms, can also benefit from lazy loading. In this scenario, new content is loaded as the user scrolls down the page. By lazy loading the content, the initial page load time is reduced, and the user can continue to scroll without experiencing a lag in performance.

    (c) **Videos:** Lazy loading is also commonly used for videos, especially on mobile devices, where data usage is a concern. In this scenario, a thumbnail image or preview is loaded initially, and the video is loaded only when the user clicks on the play button.

    Overall, lazy loading is a powerful technique that can significantly improve web performance by reducing the initial page load time and improving the user experience.
5. **Use a Content Delivery Network (CDN):** A CDN can improve web performance by caching content closer to the user, reducing latency, and speeding up content delivery. When the user is far from the server geographically, latency increases. Moreover, request load could also impact the content serving time. The loading speed of frontend content, including HTML pages, stylesheets, JavaScript files, and images, can be optimized using a CDN. A content delivery network (CDN) is a group of servers distributed across several geographical locations that store a cached version of the content to deliver fast to the end-user. CDN redirects user requests to the nearest server.

By following these best practices, you can significantly improve web performance from the frontend, providing a better user experience for your website visitors.