How to Improve Image Loading Times

We’ve all had the experience of visiting a website in hopes of buying something only to be put off by the terrible image quality — if the pictures loaded at all. When a webpage looks outdated or unprofessional, it sends visitors scrambling to hit the back button.

Images are especially important on websites that sell things. Customers will understandably hesitate to purchase things if they can’t confirm what the items look like before placing their orders. 

Pictures are also useful for educational purposes, especially as people learn about unfamiliar topics. If someone’s reading an article about types of construction equipment, but they have little or no background knowledge on the matter, seeing what each piece looks like would undoubtedly increase their understanding. 

Why Does Image Loading Time Matter?

People don’t like to wait. Many will get frustrated if images load too slowly. Relatedly, since the internet has so many other options, some users will simply go to competing sites rather than deal with the slowness.

Fast, seamless image loading says a lot about a website — and the organization that owns it. It implies that the company puts as much effort into its products and services as it does its online presence, making visitors feel secure and improving the odds of making a sale. 

A 2017 Google study found that as page loading speed went from one second to three seconds, the bounce rate increased by 32%.

Besides hurting the overall user experience, slow-loading images can negatively impact a site’s search engine rankings, making it harder for potential visitors to find it. Pictures can do a lot to make a site more engaging, leading to longer dwell times for the people visiting it. However, slow loading times can eliminate those benefits, making it harder to get enough repeat traffic. 

Fortunately, there are some actionable things someone can do to make images load faster. Trying several of those strategies can indicate what works well and what doesn’t. It’s a good idea to measure the loading times of images and the whole site before making any changes. Pay attention to the entire site size and the overall loading time. Those are the two metrics that will change when people make conscious decisions to improve image-loading results. 

With that in mind, here’s how to improve image loading times. 

Optimize Images

Optimizing an image means to reduce its file size without compromising its appearance. Using efficient image formats — such as JPEG for photographs and PNG for logos, charts, illustrations, and other web graphics — is one way to optimize images. Making pictures smaller also helps them load faster, as does optimizing their compression settings. 

When optimizing images to improve their loading times, it’s critically important to make sure they load correctly on mobile devices. Mobile web traffic surpassed desktop browsing in 2016, so more people will be viewing images from their phones than their computers. Keep this in mind when resizing or compressing images. Use CSS media queries or the <picture> element to display different image dimensions for different screens. 

It’s also a good idea to learn what Google takes into consideration when ranking pages that feature images. Although the tips don’t relate to loading times, following best practices will help a newly improved page rank better in search engines. That approach will bring all-around benefits and not provide the wrong impression that trying to make images load faster caused the site to fall in the rankings. 

Be sure to choose the most appropriate file types when embarking on an image-optimization strategy. For example, PNG images are high-quality options, but they’re larger than JPGs. If a site has lots of animated images, the GIF file format is the best choice for those. 

Consider using one of the many free or fee-based image optimization tools. They’ll cut down on some of the manual tweaks, especially since these products often have preset options to achieve particular results. 

Lazy Load Images

Whether people are shopping for things online, researching topics for a college assignment, or catching up on the latest news, they usually scroll through the content rapidly. Internet users have become skilled at scanning the material as it moves down the screen, only stopping when they find something of interest. 

Lazy loading prevents images from appearing until they’re almost in a site visitor’s frame of view. In most cases, there’s no reason to load every image on a webpage before the site opens. This is especially true with mobile devices. Visitors will be scrolling downward with a narrow frame of view on their phone, so the images at the bottom of the page can be loaded last without affecting user experience. 

Only use lazy loading for images closer to the middle or bottom of the page. That way, visitors won’t have to wait for the site’s main graphics to load when they first click on the page.

Many image optimization tools come with lazy-loading options. However, some site owners and developers don’t activate them due to a misunderstanding about how they work. Turning lazy-loading features on or off is usually done with a click or two, so there are no worries about making major changes to a site by giving them a try. 

Employ Asynchronous Loading

The concept of asynchronous loading is similar to lazy loading, but it’s not quite the same. Typically, a website loads by fetching images one at a time, waiting for each to finish loading before retrieving the next. This process can be tedious. The more images are on the page, the longer it takes to load each one in its full resolution. 

Asynchronous image loading lets a website retrieve multiple images simultaneously. As one image begins to load, the site goes ahead and grabs the next one to let it start loading as well. Fetching several images at the same time improves image loading speed.

Use a Content Delivery Network (CDN)

A CDN is a network of data centers and proxy servers located around the world. CDNs improve image loading times because no matter where a site’s users are located, the site always loads the same way. When a visitor requests an image, the CDN delivers it from the nearest server. This technique reduces the overall distance the image has to travel from server to computer, thus improving image loading times. 

For example, if a site normally takes one second to load in Houston, two seconds in Cape Town and three seconds in London, a content delivery network makes it so the site takes the same amount of time to load. When people see a site’s pictures loading quickly, they’ll have fewer opportunities to second-guess their reasons for being there. 

Some CDNs are fee-based, posing challenges to web developers on tight budgets. However, there are also plenty of free options, including those that work on popular platforms, such as WordPress. 

Implement Browser Caching

When someone visits a website, a browser cache saves copies of the site’s images on the person’s local computer, reducing server requests and speeding up subsequent image loading. How does it work?

On a person’s first visit to a site, their browser downloads an image, such as the website’s logo, from the site. Their browser then stores the file in the local browser cache. The next time the visitor clicks on the site, their browser loads the logo from local storage — the browser cache — rather than downloading it a second time. 

Web designers should configure a web server to set appropriate caching headers for images. Specifying a long expiration time for images means future visits to the site will avoid unnecessary image downloads. 

Try Tools That Allow Bulk Edits

If your website has hundreds or thousands of images, the prospect of changing all of them for the sake of better image-loading results may seem daunting and too time-consuming a task.

Fortunately, many of the free and paid tools available allow working with many images simultaneously. Some options do not have file number or size caps, allowing people to be more productive. However, since those will apply changes to all files, it’s essential to spend enough time learning about all the features and determining the best settings to try.

Consider setting goals of editing a specific number of files per day to make the images load faster. Getting through the task progressively like that will increase motivation by making it more manageable, especially if the website has a small team behind it. Plus, noticing the loading speed gradually improving will show people their time and tweaks are well worth the effort. 

Take Advantage of Preloading

Web designers should specify important images to be preloaded through JavaScript or HTML tags. Doing so tells the browser to retrieve images in advance, making them readily available when requested. This can improve image loading times significantly.

Combine Multiple Images

Loading multiple small images reduces image loading speed. Combining multiple smaller images into one larger image sprite reduces the number of image loading requests, thereby speeding up load time. 

Replace Images With CSS3 Effects

Another technique is to use CSS techniques instead of an image file, removing the need for image loading altogether. Designers can replace images with shadows, gradients, and rounded corners, eliminating the need for additional image requests. 

Minify HTML, CSS, and JavaScript

Smaller files make for faster loading times for an entire webpage, including any images. Minifying HTML, JavaScript, and CSS files reduces their size by removing unnecessary code structures, comments, and whitespace. Minification removes redundancies without affecting how the browser processes the resource.

Tools for minifying CSS include CSSO and CSSNano. UglifyJS and Closure Compiler are great resources for minifying JavaScript, while HTMLMinifier works well for HTML. 

Leverage Next-Gen Image Formats

Next-gen image formats allow developers to compress images without losing quality. They also make it possible to upload high-quality photos without slowing down the website’s loading speed. Image formats like WebP and AVIF are web-optimized image file formats that consume less network data than PNG or JPEG, allowing sites to display crisp images without sacrificing speed.

One downside of AVIF is that many browsers do not support it. In contrast, WebP works well with most popular browsers. WebP may be a better choice than AVIF for this reason. 

Choose Responsive Images 

People view website content on a huge variety of screen sizes. Although mobile devices are most popular now, there are still no standard dimensions even across those products. Plus, some people still view web content on their laptops or desktop computers. 

These facts illustrate why it’s so necessary to select responsive images for a modern website. They automatically adjust to a person’s screen size for the best viewing experience. 

The main benefit of responsive images, considering the topic at hand, is that they accelerate image-loading times and curb unnecessary data usage. The alternative is that it takes a longer time and more data to get a large, high-resolution image properly sized for a small screen. 

People can quickly create and work with responsive images by using a specialized tool. Many of them are available for free and easily found through a quick web search for “responsive image tools” or a similar phrase. 

Use Compatible Website Themes

Another way to improve image loading times is to improve page loading speed overall. When using WordPress to design a mobile page, for example, developers should use responsive WordPress themes to ensure the site loads correctly. 

Checking the customizer or theme options helps determine if a WordPress theme is mobile-friendly. External plugins like Any Mobile Theme Switcher and WP Mobile Detector can also help create responsive sites for mobile devices. 

Enable HTTP/2 or HTTP/3

HTTP/2 and HTTP/3, newer versions of the classic protocol that transfers data over the internet, are much more efficient at handling simultaneous requests than HTTP/1.1. As a result, they help everything on a page load faster, including any images. 

Improving the Visitor Experience

Site visitors are potential customers, business partners, investors, and employees. A website is often their first point of contact with a business.

Improving image loading times makes a website function better and look more professional, leaving a positive impression on anyone who visits. Plus, now that mobile browsing has surpassed desktop searches, it’s more important than ever to optimize images and ensure they load correctly. Web developers can combine several strategies to get the fastest possible image load times.