February 8, 2023 by Testomato

Four Ways to Improve Website Loading Speed Through Image Optimization

The speed of your website is important. Do you know that a one-second delay in page load time can result in 11% fewer page views?

Four Ways to Improve Website Loading Speed Through Image Optimization

So even those few extra seconds can be critical in engaging visitors as well as boosting overall sales.

Having a fast website is crucial. More than just boosting your rank in Google, it also drives in more conversions and boosts overall sales. Whether you sourced your photos from stock photography websites or you decided to DIY your product photos, optimizing images is very important to make sure that your website performs with speed.

Basically, image optimization is the process of compressing image files to reduce their existing file size, and yet maintain the image’s overall quality as much as possible.

You may wonder if the final result looks too different from the original image, why is there still a need to optimize? While compelling, high-quality images are a huge factor in drawing in visitors to your site, there is a downside to it. Images have big file sizes, which can significantly affect your site’s overall performance. After all, a slow-loading site will have higher bounce rates ‒ meaning people will leave your site even before they get to interact with it.

Here are four ways to reduce website loading speed through image optimization:

Your File format

JPEG is the best format to create a lighter image. It compresses the image and you can choose the quality degree.

If you want an image to have a more transparent background, then you need to use a PNG file format. Although it creates higher quality images, it doesn’t compress images as a JPEG does and usually has heavier files. PNGs are used in smaller amounts and are for smaller images.

GIF is usually used for animated images.

If you want to know the best file format, usually, in most cases, JPEG will always be the better choice. If you need an image with a more transparent background, a PNG format will be a better fit.

Quality of the Images you Post

Images can play a vital role on your website, and a high-quality photograph that is professionally-taken is an advantage. There are a lot of product photography guides on the internet so it’s not a big deal to have one for your website.

Almost 96% of the internet’s entire image traffic is from GIF, PNG, and JPEG formats. Note that if you’re using third-party tools will make the end product of your image much larger.

Since GIF and PNG are lossless formats, during the compression process, there will be no visual modification on the images. If you’re using still images, PNG does an excellent job with the compression ratio as well as the overall image quality. On the other hand, if you’re working with animated images, to achieve a better compression, a video element is preferred over a GIF.

Use a Plugin

Plug-ins are a great way of handling image optimization directly from your WordPress dashboard. Moreover, it automates the entire process. There are different options available out there in the market:


Great for beginners, it offers superb customization and functionality. Some of its key features:

●     Have backup features and bulk optimization

●     Has a method that automatically resizes images

●     Includes three levels of compression: aggressive, lossy and ultra


ShortPixel is an intuitive and compressive plug-in that’s great for both beginners and experts alike. Some of its features are:

●     An option to convert to the WebP format

●     Has no file size limit for images

●     Provides free optimization credits for non-profit organizations


Kraken.io offers more advanced options for automatic optimizations. Like the other solutions available, you can bulk-optimize images with this plug-in.

●     Automatic resizing and rotation options

●     Keeps image metadata tags

●     Augments resized images to avoid downsampling and ‘haloing’

Compress JPEG & PNG Images

A plug-in that as made by the developers of TinyPNG, its user-friendly features are a great option if you are already familiar with the TinyPNG website.

●     Has free 500  image optimizations monthly

●     Absolutely no restrictions on file sizes

●     Converts image automatically from the CMYK to RGB color modes

●     Automatically resizes images

Optimize for a Great Conversion

Image optimization is a vital factor if you want to build a highly successful website. It is an art that you need to master to attract potential customers to your site. After all, having highly optimized images means it reduces the overall site load time. Thus, there are high levels of user engagement on your site the moment visitors step in with low bounce rates.

**About the Author: Lili Griffin is an e-commerce developer and Adwords specialist.

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