Image Optimisation: Is It Truly Important For SEO?
Every website is likely to have images, but did you know that they can be optimised? Image optimisation is an important part of the web building process, with the potential to speed up loading times across your website, encourage Google to list your pictures in Google Image results and simply attract the eye when a visitor does click through to your site.
With 81% of all visitors typically skimming over content, but posts featuring images said to produce over 650% higher engagement, it seems to be a no brainer that visual content is an important part of the web design process. Optimisation, however, isn’t as common as you may expect. We’re taking a look at what image optimisation is, and whether it can have an effect on your SEO.
What Do We Mean By Image Optimisation?
Image optimisation is, in technical terms, the act of reducing the file size of the images you’re uploading to your website. However, there’s a lot more to an optimised image than a reduced file size. From the alt tags under the images to the dimensions of the picture on the page, there are a number of things you can do to optimise your images not only for usability and fluid functionality but to appease search engines. Even simply using stock images can have an effect on how your users view your website and, of course, your brand.
Optimising your images can include:
- Choosing the right file names
- Reducing the file size
- Choosing the right format
- Optimising your captions
- Adding alt text and title text
- Using image structured/schema data
- Checking the images are responsive
- Keeping the image relevant
Can It Help SEO?
When we think about SEO, a lot of us tend to lean towards text, whether that’s length, content or keywords, but the images we use can also have a substantial effect on how our websites perform in the SERPs.
Most web users want pages to load within 2-3 seconds and any pages, whether desktop or mobile, that can’t offer that kind of speed risk page abandonment. In fact, for every additional second a page takes to load, you can lose upwards of 10% of your traffic. When images take a while to load, this can slow down the overall page speed considerably. Google considers slower loading speeds as being against user experience, which is one of the key ranking factors that webmasters need to pay attention to today.
What’s more, mobile-first indexing has increased the urgency for improving your page speed considerably. Those browsing on mobile want near-instant results more than those on desktop, usually because they are on-the-go or simply making a quick search. The faster your page can load and the better users respond to it, the higher you may find yourself appearing in the SERPs.
How To Go About Optimising For Your Website
So, we’ve established that image optimisation can help your SEO, but how exactly do you go about getting started? From ensuring that all of your 3. images have optimised names and reducing the overall file sizes, here’s what you can do to get started:
1. Name Your Images And Optimise Alt Tags
When you create or save an image, it’ll likely have a generic name assigned to it (e.g. IMAGE356.jpg) and while this may be all well and good within your personal documents, Google and other search engines can actually utilise this name to determine the content of the image. For fashion websites, for example, an image with a name such as Black-Maxi-Dress.jpg, or frankly any product name, can ensure that Google associates that picture with the subject matter on the page more effectively.
Google can determine the content of a picture to some extent using machine learning technology, however, it isn’t always accurate. Two products that look similar could be listed incorrectly for some search queries and for this reason, giving the search engine a helping hand can work to your benefit.
The same can be said for alt text. This text is essentially what will be displayed if the image cannot load and what is read by screen readers. The alt tag should clearly describe what is in the image and can be as simple as “This is an image of a black maxi dress”. This will give Google a better context, improve accessibility across your site and be seen as a better user experience overall.
2. Reduce File Size
The size of your files has the potential to slow down your website considerably. While reducing the file size may reduce the quality, it’s entirely possible to dial down the quality and the size without there being any noticeable differences to the human eye. This is one of the core methods for optimising images, with Google even recommending open-source tools to help with this task. These tools essentially take the image and compress the size down to reduce the overall size of the data. This, in turn, leads to faster loading times on your website.
When you compress an image, there are two kinds that you can see – Lossy, and Lossless.
Lossless: This filter compresses the data but doesn’t reduce the quality of the image. Generally, this is the best choice for those wanting a quick compression without risking the image itself, however, it will need to be uncompressed before it can be rendered.
Lossy: This method of compression essentially eliminates the data as opposed to compressing it. However, this does reduce the quality of the image, so it’s important to be careful with how much you choose to reduce the image before you lose too much of the quality.
3. Choose Image Dimensions Wisely
With the sheer number of screen sizes available on the market today, browsers have learned how to resize images (if you have a responsive enough design). However, while this stops the page trying to show a 5000px image on a 720px screen, it doesn’t cut down the size of the image completely. In fact, the 5000px image will still need to be loaded, before it can be reduced to fix the size of the screen.
In other words, a larger image than the space available can cause slow loading which, as mentioned before, can lead to increased bounce rates and reduced conversions. To avoid this, you’ll need to get smart with design, resizing your images to fix the maximum width of your site, or of the space in which you want it to appear
4. Choose The Right File Type
While there is technically no perfect format for all of your images, there are a number of suggested combinations to truly optimise each picture individually. This includes:
- PNG – for images with transparent backgrounds
- JPEG – larger photos or illustrations.
- WebP – Smaller file sizes, but high-quality results.
- SVG – For logos and icons
You should also consider tracking where the majority of your visitors come from – are they on mobile, or on a particular browser? Some devices and browsers handle certain image types better than others, so this can also influence which image types you can or should use to better optimise your site for visitors.
Whether you’re redesigning your site and want to ensure everything is optimised from the very start, or you’re looking to improve your loading speed and ranking opportunities, optimising your images can help you get ahead of your competitors. With the potential for higher rankings, better relevancy of results and the chance to make it into Google’s Image search, the possibilities are endless.