Optimising Images for your Website

Optimising images on your website can have a big impact on your site speed and SEO. There are several ways to perform optimisation. In this article, we look at the best file formats and sizes to use and provide helpful info on free and low-cost editing tools to optimise your images. 

Why Optimising Images is Important?

A reason someone might leave your website is because the load time is too slow. One factor that contributes to a slow website is image size. Your website is a representation of you and your brand, so it is important to give your potential customers and clients a good user experience from the start.

File Format

WEBP, PNG and JPEG are the best file formats for the web. JPEG is good for photos or colourful images; PNG is perfect for simple pictures or transparent images. There are other file formats such JPEG XR but be careful about using these kinds of formats, as they may not be supported on all browsers. 

File Size

Best practice is to keep the total weight of a webpage under 1 or 2MB. If your page has a lot of images, take that into consideration as you optimise. Ideally, you want to reach the perfect balance between a low file size and good image quality. The size will depend on where they are situated on your website. The optimal file size should be no more than 300kb (where possible). Fullscreen background or hero images should be between 1500 pixels and 2500 pixels wide, and other images should be no wider than 800 pixels. 

Image Optimisation Programs and Tools

There are many online tools available to optimise images. Software such as the Adobe Creative Suite and Photoshop can cost a lot of money. If you are a WordPress user, there are plugins that can optimise images from your media library. But just note, these plugins can take up a lot of space, which can also affect website speed. Listed below are some low-cost and free online tools you can use to optimise images. 


TinyPNG is a free web app that reduces the size of your PNG files. You upload your image or drag and drop to the website. They also have a sister website, TinyJPEG, for (you guessed it) JPEG files. 

Screenshot of TinyPNG a website to Optimise Images


Optimizilla converts and compresses both JPEG and PNG files. It has a slider feature which allows you to see the before and after, so you can preview the image. It is great for batch processing, as it allows you to upload 20 images at a time. 

Screenshot of Optimizilla a website to Optimise Images


JPEG.io converts any file format into a JPEG. To use the optimiser, you can drag and drop or upload your PNG, GIF, TIFF, SVG or even your PSD files. It will convert your images before compressing. 

Screenshot of JPEG.io a website to Optimise Images


Kraken allows you to choose between lossless and lossy compression modes. Lossless has no drop in quality. Lossy has a small drop in quality but cuts the image size by almost 90%. It allows you to convert JPEG, PNG and GIFs. It is free for files up to 1 MB, but if you require conversion of larger files, you will need to sign up for a pro account. 

Screenshot of Kraken a website for Image Optimisation


If you have not been optimising images for your website, now is a good time to get started. It will make a big difference to your website speed and SEO. 

We hope this article has provided some useful information about image optimisation. See our SEO Checklist for Small Business for helpful tips on improving your search engine ranking.  

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About Inkt Creative

Inkt Creative is a full-service Web Design and Content studio based in Bendigo, Australia. We specialise in Website Design, WordPress Development, Graphic Design, Content Writing and SEO.

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