Often the role images play in SEO is underestimated. But rather than simple place holders or visuals to make a page look pretty, strategically-chosen optimised images can have a profound impact on site user experience, performance and ranking opportunities – 3 key areas of SEO. As SEO specialists, whether we’re conducting an audit on an existing site or designing a new one, visual content is one of the first things we assess because images can make or break a successful SEO campaign.
Here’s how images can impact your site’s SEO and the top ranking factors you don’t want to miss.
What is image optimisation in SEO?
Image optimisation is an SEO strategy. It involves ensuring the images you use on your website contribute to optimum user experience, website performance and search ranking through techniques like reducing image file size and adding the metadata needed for image search.
How do images influence SEO?
Images influence SEO in three ways:
1. Load Speed
Page load speed is a major ranking factor both on mobile and desktop sites. High-resolution images can be massive files. So, although your professional product pics might look amazing, if you’re uploading them straight to your site, you’re adding a lot of weight and time to your load speed, which will negatively impact your ranking.
2. User Experience
One of the reasons load speed is so important for search engines is that it affects user experience (UX), and search engines like happy users. With as much as 40% of users giving up on websites that take more than 3 seconds to load, fast-loading images are a critical part of a positive impression of your site. What’s more, using unique, relevant images can enrich your content and contribute to a positive UX by keeping users engaged, supporting your message and even guiding people through the buying process.
3. Indexable Content
Studies suggest that image searches represent 20% of all searches conducted online. So images can extend your rankable content and present extra opportunities to appear in the all-important SERP. This is particularly important for products where aesthetics drive buying decisions like fashion, homeware and motoring.
So if you want your images to work to your advantage and harness their true SEO power, they need to be fast, UX-enhancing and findable on image search. And here are the top ranking factors you need to consider to make your images SEO friendly.
How to make images SEO friendly
1. Image Marketing Power
Images are valuable marketing tools. They don’t just break up text. Your images are on your website to enforce your brand and bring your products to life. Using brand specific, aspirational images on your site can even help guide users through the buying process. And the stronger your images are at supporting your brand, the more they will improve user experience, increase the amount of time users stay on the page, boost your brand authority and increase the shareability of your content – all of which contribute to your ranking in search engines.
2. Image Uniqueness
How unique your images are will also influence your rankings. Boring stock images that are used across hundreds of sites limit your ranking opportunities and add nothing to your marketing message. Use your own unique images where possible, and if you have to use stock images, don’t forget to credit the owner appropriately.
In fact, images don’t always have to be images. You can use graphs, charts, graphics, embed social media posts or even add gifs. All of these will enrich your web pages and provide more content to rank in image search.
3. Image Relevance
Be careful not to get too carried away with images though – don’t add them just for the sake of it. They need to be relevant to the page context to achieve that glorious marketing power we talked about earlier. And from a search engine point of view, the relevance of images to the surrounding content on the page can help boost your ranking for specific keyphrases. For example, if you have an image of a kitchen island on a page that talks about kitchen islands, this reinforces the relevance to the clever little Googlebots who will rank your image better for that phrase as a result.
4. Image Captions
And one way to increase image relevance to surrounding content is to include captions. Simple captions that describe what’s in your image add more relevant text to the page.
5. Image File Size
We live in a fast-paced digital world where people (and search engines) want information almost instantly, so load speed is a significant ranking factor as mentioned before. And image files can be huge, which can really slow down your site.
Ideally a page should be no more than 2MB, so if you’re uploading images of 25MB, your site will be sluggish – negatively impacting your ranking and user experience. If you upload an image to your site directly from a digital camera, for example, it will be the highest possible quality and include a tonne of metadata like camera type, geolocation, etc. All of this is overkill for your website that adds vital seconds to load speed.
To ensure your images aren’t slowing down your site, you need to resize and compress your files to find the sweet spot where images still look great from a user perspective but the file is more digestible from a loading point of view.
And make sure your images are responsive too, so your content displays properly on mobile.
6. Image File Type
There’s no one ideal file type for images – it all depends on what your image is. But choosing the wrong one can add unnecessary weight (and load time) to your site.
Here are the most commonly used image file types and where they work best:
- JPEGs are great for big images as you maintain a good degree of quality while achieving a smaller file size.
- PNG files are ideal for logos and line drawings.
- WebPs are another possible file type when quality is important, but they are not currently supported by browsers like Safari, iOS Safari and Internet Explorer.
- GIFs are best for animations.
- SVG files are automatically scalable in browsers and photo editing tools, and they are indexed easily by search engines. They’re ideal for logos or icons, but they do require specialist coding onto the page.
7. Image Recognition
Search engines like Google are getting smarter by the day and they now have image identification capabilities meaning that they tell what your image is even if there’s no metadata. You can upload any image to Google Vision API and they can tell instantly what the image is. So if you want more chances of Google finding your images this way, it pays to keep you images simple and unambiguous.
8. Image File Name
Despite advancements in image recognition, it’s still a good idea to add the relevant metadata to your images to ensure search engines know exactly what your image is and can rank it accordingly.
Calling your file DSC8456 says nothing about your image. Name your image files simply and correctly. And if your images are relevant to your content, your file name should include your target keyphrase too. There’s no need to stuff keyphrases in there though, no one likes a spammer, and search engines will penalise you for it.
For example, the image below from our friends at Base Campers could be named ‘dog-friendly campervan’ – simple, relevant and including the focus keyphrase.
9. Image ALT Text
ALT text in images is important for users and search engines alike. ALT text describes an image, and it’s predominantly needed by visually impaired users who have screen readers.
You need to keep ALT text as descriptive as possible while still keeping it concise. Describe what is in your image clearly, but you don’t have to use full sentences – you only have around 125 characters. Going back to our example above, the ALT text could be ‘man and dog happy in camper van’.
When you’re done, ask yourself if your ALT text would make sense if you couldn’t see the image. And again, if you’re using relevant images, you should be able to include keyphrases in your ALT text too. But remember, no stuffing! Write for the user first, not the search engine.
10. Image Structured Data
Including structured data with your images gives you more chances of Google displaying your listing as a rich result, making it look more compelling to users and increasing your chances of catching the click. So put the cherry on top of your image SEO and add structured data.
11. Image Meta Tags for Social
And just to add some sprinkles for good measure, you can add meta tags to the header of your web pages for Open Graph and Twitter Cards to ensure your images appear in social shares too. Open Graph’s meta tags are recognised across all major platforms like Facebook and LinkedIn. Although this might not be a direct ranking factor, social media sharing, engagement and click-throughs are key traffic sources for your content. And the more traffic you get, the better your ranking.
The Key Points of Image SEO
Phew! That was a lot of information to process, so let’s recap. Here’s a summary of what you need to do to hit all of the top image ranking factors:
- Ensure your images support your marketing message
- Use unique images
- Keep images and content relevant
- Include captions to add relevance
- Reduce file size
- Choose the right file type
- Keep images simple
- Name files appropriately
- Add Alt text for visually impaired users
- Don’t forget structured data and meta tags for clickable, rich results on search and social.
Image Optimisation Overload? Call the Specialists…
We’ve been building optimised websites and crafting effective SEO strategies for over 20 years. If you’d like to talk more about image optimisation, high-performing web design or SEO, give our specialists a call today. We’ve got all the SEO expertise and web design wisdom to give you the boost you need – check out our results to see for yourself.