Image Optimisation Tutorial – SEO Impact

What is image optimisation?

This can simply be described as customising images to suit various device types and improve loading speeds along with SEO efforts. It can also enhance the user experience and improve find-ability within search results. 3 commonly applied optimisations include adjusting the size, quality and the keywords associated with an image.

How to optimise images for faster loading webpages?

If we have taken an image from a digital camera to use on a website, the size and quality will need to be reduced to suit the internet or a webpage may take along time to load. The photo dimensions might be 2048 x 1536 pixels and 2000 kilo bytes in file size. By reducing the image size to 500 x 375 pixels we have already reduced the file size to 500 kilo bytes. By reducing the quality we can save even more file size and reduce the image from 2000 kilo bytes to potentially as low as 30 kilo bytes. That is a massive reduction and will be reflected in how fast a web page loads. There are various programs that can be used to optimise images, including Fireworks and Photoshop to name a few. Compressjpeg is another great way to reduce the image quality of a jpeg, png and pdf to the maximum level for improved speed test scores and loading times.

Image size can make a big impact on how well an image displays on various devices. It’s worth testing a webpage on a few different sized screens to make sure that it looks good and loads quickly. For the best results, we want to reduce images to the smallest possible size, while still displaying well on the larger sized screens.

Image quality is another great way to reduce the file size. If an image is 100 percent quality and we reduce by 25 – 80 percent. This may not affect how the user sees it on a computer or portable device. Photos and images can often be high quality and may not be suitable for a high performance website. Reducing the quality to a level that looks good enough for the end users while drastically reducing the file size is a great way to speed up a webpage.

SEO image techniques

Make your webpages stand out by adding compelling and descriptive images. Not many users likes to see a page with only words. On the other hand, search engines won’t give relevance to a page that has all images without any word content.

Image title text is another way search engines can identify the topic of a page and its content.

Image Alt tags are an up to date method that help to show relevance to the webpage contents. Search engines will read the ALT text and they can also help a webpage to be placed higher in the search results.

Image captions help users to identify the subject of an image and this can certainly improve the user experience. Search engines also pay attention here to, so the next time you upload an image consider wether a caption can enhance it or not.

Social shares will also look more attractive and appealing with an image rather than just text. Make sure each webpage has a share friendly image. It’s also worth testing the image appearance on various social networks.

Image file names can include two or three keywords that give relevance to the image or to the content topic. Remembering that it is a good practice to separate the keywords with hyphens when naming the files.


By implementing these methods, a site will be sure to improve the user satisfaction and search engine visibility. Image optimisation plays a big role in creating a site that loads fast and displays well on various devices. ALT text, titles, filenames and captions also play a big role for website find-ability as search engines use these signals to find relevance in the content and index it accordingly. Image optimisations should not be over looked when creating a successful website that will generate large amounts of online traffic.