How can you minimize HTTP requests to speed up your website?

1 Combine Files

Combining files is a powerful method to reduce HTTP requests. Instead of serving multiple CSS or JavaScript (JS) files, merge them into a single file for each type. This way, your website will only request one CSS file and one JS file, instead of several. For instance, if your site uses multiple CSS files for different parts of the layout, you can concatenate them into one comprehensive stylesheet. Similarly, you can combine various JS libraries and scripts into a single file. This approach not only cuts down on HTTP requests but also helps with maintaining your codebase.

2 CSS Sprites

CSS sprites are another effective tool for minimizing HTTP requests. By combining multiple images into one larger image and using CSS to display only the relevant part where needed, you effectively turn many image requests into a single one. Imagine a navigation bar with different icons for each item. Instead of loading each icon separately, you can create a sprite that includes all icons and use CSS background-position property to display the correct section of the sprite for each item. This technique is particularly useful for sites with many small images, such as icons or buttons.

3 Inline Images

Inlining images using Base64 encoding can be a smart way to cut down on HTTP requests for small images. Instead of requesting an image from the server, you embed it directly into your HTML or CSS using data: URIs. This method converts the image to a string of text, which can be included directly in your code. While this increases the size of your HTML or CSS file, it eliminates the need for separate HTTP requests for those images. Use this technique sparingly, as it can increase the size of your files, which might negate the benefits if overused.

4 Minify Resources

Minifying resources is a straightforward yet impactful approach to reduce HTTP requests. This involves removing unnecessary characters from your HTML, CSS, and JavaScript files without changing their functionality. Tools are available that automate this process, stripping out comments, white spaces, and line breaks, resulting in smaller file sizes and fewer requests needed for separate script or style files. By serving minified versions of these resources, you ensure faster loading times and a more streamlined user experience.

5 Use Caching

Leveraging browser caching is an excellent way to minimize HTTP requests for repeat visitors. When a user visits your site, elements like stylesheets and images are stored in their browser's cache. On subsequent visits, the browser can load these files from the cache instead of making new HTTP requests to the server. You can control caching behavior using the Cache-Control header in your server's response. Setting an appropriate expiry date or maximum age for your files ensures that browsers won't request the same resources too frequently.

6 Prioritize Content

Prioritizing content is about loading the most important elements of your website first. This technique involves organizing the order in which resources are loaded to ensure that critical content is displayed as quickly as possible. For example, you might load essential styles and scripts in the head of your HTML document and defer less critical ones until after the page has rendered. Additionally, lazy loading non-essential resources, such as images below the fold, means they are only requested once the user scrolls down, reducing initial HTTP requests and speeding up the time to first paint.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?