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The ultimate guide to image optimisation

October 10, 2023

No matter what web page you’re adding an image to, it’s incredibly important to ensure it’s optimised for SEO (Search Engine Optimisation). And when it comes to image optimisation, you’re contributing your website’s SEO more than you might think. For example, not only are you helping search engines better comprehend your site and content, but you’re also increasing your visibility in image search results, which is beneficial for increasing interest in your products and services.

In this blog, we provide you with the ultimate to image optimisation including the importance of SEO image optimisation as well as sharing some top tips on how you can optimise your images for the web.

Why is image optimisation so critical?

The technique of search engines assessing and ranking websites can be complex, but effective SEO enables your audience to find you quickly online. It’s one of the most effective digital marketing strategies for achieving a top ranking in search engine results pages (SERPs).

Many people believe that SEO is solely concerned with title tags, headers, and body content and while these are some of the most crucial elements of SEO, it doesn’t end there. Image SEO is vital because search engines can’t analyse images the same way a human can and image optimisation is the only way to ensure that.

As mentioned previously, image SEO is another way to boost your ranking in search engine results which in turn, can increase traffic to your website, boost engagement and ultimately lead to more conversions.

Although the technique of SEO image optimisation can require some expertise, there are some simple best practices you can carry out to ensure your images are optimised for search engines.

Our top tips for image optimisation

Be familiar with your keywords and phrases

You should conduct some research, just as you would for the rest of your website’s SEO. You’re probably already aware of the primary search terms people use to locate you online and it’s even better if you’re familiar with the keywords you rank for. So with this knowledge, you’ll already know which keywords to use when optimising your images for SEO.

If you’re uncertain about your keywords, now is the time to conduct some keyword research. Utilise Google’s Keyword Planner, SEMRush or any other keyword research tool to determine what search terms are being used relating to your business. Once you’ve identified your target keywords, you’re ready to tackle the process of SEO image optimisation.

Name your images appropriate for SEO

We understand the temptation to go down the easy route and name your images using the default title provided or something basic like “image2.jpg.” However, this is not ideal because search engines study image file names, so you should ensure your images are named appropriately for SEO.

Be sure to include one of your target keywords in the file name if it is relatable to the image. That being said, avoid using random keywords to enhance your image SEO. While a search engine may not immediately recognise a description is irrelevant, keyword stuffing is never a smart idea.

Add your images to your sitemap

Since search engines can’t gather information from images, you must include as many hints as possible about what they display. As a best practice, Google suggests generating image sitemaps when adding an image to your website.

This means that you will need to adhere to their guidelines when uploading an image to your site, otherwise your images won’t perform as effectively as they could in search engines.

Enhance your image alt tags

As search engines can’t process visuals in the same way a human brain can, they rely on alt tags to tell them what is being displayed. So as part of your SEO image optimisation strategy, each image on your site should have its unique alt tag explaining what it is showing, with as many relevant keywords as possible. 

Not only will this provide a huge benefit for your website’s SEO, you’ll also improve your accessibility and enhance the experience of those who are visually impaired. 

An alt tag is displayed when users hover their mouse over an image when everything is configured correctly. However, if a browser can’t display your image, an alt tag is the text that appears in its place.

Remember, you should never utilise alt tags to fill your site with your target keywords. Google and other search engines will ultimately catch on and this will harm your SEO in the long term.

Don’t forget to include image title tags

Along with alt tags, title tags should be used when you optimise your images for the web. Many people get these two parts mixed up; however, unlike alt tags, title tags won’t substitute for images that can’t be displayed correctly.

This means your title tags don’t have to be keyword-heavy. You can utilise them to communicate directly with users and they can be written similarly to image captions or used to offer further explanations.

Avoid hiding your text with images

Hiding any text with an image is a black-hat image SEO technique that will harm your SEO efforts. You might want to substitute an image for the initial page heading, generally known as the H1, but we recommend avoiding hiding your header text. If you insist on wanting to use an image as your header, be sure to properly identify the image to reap the benefits of SEO image optimisation.

Always compress your images

Rankings in search engines are determined by a variety of criteria, including website load time. When image files on a web page are huge, the page will take longer to load. If your pages load slowly, your rankings may suffer as a result. And if they take so long that users become frustrated and exit before seeing your content, your rankings may suffer even further.

Reducing the file size of your images ensures your web page loads quickly. There’s no hard and fast rule about file size, though anything more than a few hundred kilobytes (KB) will certainly slow down your site speed. There are many free online tools you can use to compress your images including Tiny PNG, Optimizilla and Ezgif to name a few.

To maintain the quality of your images, aim to keep them as clear as possible and reduce the file size to the point where the quality decreases. You’ll also want to avoid changing the file type to anything that would result in a drastic change in look. JPGs are normally a safe bet because they provide the highest quality at the least file size, but other file formats also work.

Need help with your image SEO strategy?

If you need help with your image SEO strategy, or you’d like us to create a wider SEO strategy and do all of the hard work on your behalf, why not get in touch with us today? Our SEO specialists can conduct an SEO audit and advise you on the best course of action for your website’s SEO. From technical SEO to on-page SEO, we can help!




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