A critical element in the success of any website is performance. When a website performs poorly and loads slowly, most visitors will have a bad user experience, which makes it increasingly likely that they will leave your website and choose to go to a competitor’s website. Nearly 80 percent of online shoppers say that slow loading will cause them to leave a website. While the appearance of your website is important, the speed and performance of the site is essential towards keeping users engaged long enough to take an action or make a purchase.

One component of a web page that can worsen site performance involves the images that you place on your website. Larger images can slow down web pages and worsen the user experience, which also serves to worsen your brand reputation. However, images and other types of multimedia are essential if you want to keep site visitors engaged. To account for the performance problems caused by larger images, it’s highly recommended that you perform image optimization by compressing images, which will improve your web performance.

It’s possible to decrease the file size of images with a script or plugin, which should solve any loading issues that have occurred after implementing images on your website. Two methods that are commonly used to compress images include lossless compression and lossy compression. Both methods are effective and can provide you with great results. The most important consideration to keep in mind when compressing images is to make sure that the image quality doesn’t reduce significantly. Making modifications to an image file can cause images to look blurry, which is the last thing you want to do when trying to keep visitors on your website. This article offers an extensive guide on the most effective techniques for compressing images and improving the performance of your website.

How to Optimize Images for Web and Performance

optimize images for web performance

When you format the images on your website, your main goal should be to reduce file size by as much as possible without sacrificing too much of the image quality. There are many different ways that you can achieve this goal, the primary of which involves compressing the images before they are uploaded to your WordPress website. Two of the more popular tools for compressing images include Affinity Photo and Adobe Photoshop. It’s also possible to compress images with plugins that you download directly to your WordPress account.

Before you start compressing images for your website, two of the most important factors when optimizing images include the type of compression that you use and the file format that you would like the images to be attached to. If you select the correct combination of compression type and file format, you may be able to compress the file size of your images by nearly five times the original size.

Quality Versus Size

As mentioned previously, among the most important aspects of compressing images is to make sure that you get the right quality and file size. While the size of your images is important to maintain a fast performance for your website, users don’t want to see low-quality images when they enter a website. If you compress an image too much, it will appear blurry with jagged edges and a large number of artifacts. At a low compression rate, you’ll be provided with a high-quality image. However, the file size will still be large.

If you want your website to have low loading times and quick performance, the images on each web page should only amount to 1-2mb in size. When using the JPEG format, you can get great image quality with optimal compression at 100-200kb. If you decide to use simpler PNG images, compress your images to less than 100kb in size, which will still allow for a high image quality. While it’s important that you strike the right balance between image quality and file size, the quality of the image is likely the most important aspect. If the quality gets too low, your brand may gain a poor reputation.

File Formats

The three main types of files that you can use for the images on your website include:

  • GIF – This option uses just 256 colors and is mainly used to display animated images. The GIF format only accommodates lossless compression.
  • PNG – This format is able to produce premium images with a higher quality. The main downside is that the file sizes will be larger. Even though the image format was created as a lossless format, it can be lossy as well.
  • JPEG – This format is able to use lossless and lossy optimization, which makes it easier to alter the quality of the image to strike the right balance between file size and image quality.

There are several additional types of formats that you could use for your images, which include everything from WebP to JPEG XR. However, only the three primary formats are supported by every web browser. If you want to use images that contain ample amounts of color, the best format would be JPEG. On the other hand, the PNG format is ideal for simpler images. Using a combination of the two file formats should make it easier for you to place numerous images on each page of your website without sacrificing performance and load times.

Resizing Images to Scale

wordpress image rescale

Uploading images to WordPress used to create numerous problems. If you attempted to upload images at a different scale, the CSS programming language would resize the images and create issues with the work that has been done to compress the images. CSS would further scale images down, which would result in blurry images with a very low quality. However, WordPress 4.4 took this option away to provide support for responsive images, which means that uploaded images will no longer be scaled down by CSS. This functionality has been present in every update following 4.4 as well.

Now, WordPress will upload images at several different sizes. The browser that the user accesses your website with will be able to select the appropriate image size while ignoring any others. Keep in mind that the original file size for the image you upload won’t be touched and will be kept in your media library. If you don’t want to keep the original file size to save some disk space, free plugins like Imsanity give you the ability to set a limit for the file size of every image you upload to WordPress.

Once you start uploading numerous images to your media library, it’s highly recommended that you look into cleaning your media library, which can be done with the Media Cleaner plugin. This type of plugin will easily identify any files within your media library that are unused, which you can safely get rid of. The unused files will be listed in the Media Cleaner dashboard for simple deletion. When you delete these files, they are sent to a special trash directory. Afterwards, you can test your website to make sure that you didn’t get rid of files that were pertinent to the functionality of your website. If you did, files can easily be restored from the trash directory.

The Difference Between Lossless and Lossy

lossless vs lossy images

It’s essential that you understand the difference between lossless and lossy, both of which are compression methods that can be used to reduce the size of your images. Lossy is a compression filter that’s able to eliminate some data from an image file. When this occurs, the quality of the image will worsen, which is why it’s important that you don’t reduce the image too much. As mentioned earlier, tools like Affinity Photo and Adobe Photoshop can alter quality settings for an image.

The lossless option is another compression filter that compresses data instead of getting rid of some of it. While the quality of the image won’t worsen when compressed, the image will need to become uncompressed before it can be properly displayed. The different tools that can be used for lossless compression include ImageOptim and FileOptimizer. No matter which option you decide to use, it’s recommended that you experiment between the two to identify which one works best for your format or image.

Image Optimization Plugins

image optimization plugins

There are a wide range of programs and tools that can be used when you want to optimize and compress images for your website. While many of these tools are paid, others can be downloaded and used for free. If you want to have as many tools at your disposal as possible, it’s highly recommended that you use WordPress for your website. With WordPress, you don’t need to perform all of the compression and formatting by hand. Instead, plugins can be used to perform many of these actions automatically.

Different plugins are able to perform different actions. For instance, some plugins will immediately optimize image files when you upload them. Other plugins will optimize any image that’s located in your media library. While plugins are reliable and efficient, you should continue to use other tools to obtain the best results. As an example, it’s important that you don’t upload too many images to your media library on WordPress, which will significantly reduce the disk space that’s available through the web host. Optimizing many of your images before uploading them to WordPress ensures that you don’t take up too much disk space.

Five of the most reliable WordPress plugins for image compression include:

  • Optimole – This is an image optimization and compression plugin that can compress, host, and resize your images. The tool is simple to use and will perform image optimization without requiring much work from you. The main issue with this tool is that there aren’t many features.
  • Imagify Image Optimizer – This is a feature-intensive plugin that offers bulk optimization and provides three levels of compression, which include normal, aggressive, and ultra. The main downside to using this tool is that customer support is relatively poor.
  • Optimus Image Optimizer – This plugin specifically uses lossless compression to optimize images. Along with providing bulk optimization, this tool is compatible with WooCommerce as well as the WP Retina plugin. The main issue with this plugin is that the free version has a cap of 100kb for the images you can upload.
  • Image Recycle – This is an automatic compression plugin that offers a suite of useful optimization features for your WordPress images. The best features include settings that allow for a minimum compression size and auto image resizing. This is largely a premium plugin. While a free trial is available for 15 days, you can only upload 100mb of images during that time.
  • Tiny PNG – This is a popular plugin that allows users to compress PNG and JPEG images. If you decide to use the free account, you can compress 100 images every month. Tiny PNG can reduce your PNG images by as much as 80 percent without losing much image quality. The main issue with this plugin is that the JPEG results aren’t as good as the PNG results.

Now that you know how to compress images and which tools are best for doing so, you should be able to improve your website performance significantly. Once these improvements have been made, you might also notice a reduction in bounce rates and an increase in customer conversion rates.

Bryan Miller of Bryt Designs Long Beach Web Design, Development, & SEO
Author
Bryan Miller

Bryan Miller is an entrepreneur and web tech enthusiast specializing in web design, development and digital marketing. Bryan is a recent graduate of the MBA program at the University of California, Irvine and continues to pursue tools and technologies to find success for clients across a varieties of industries.