This article is still as important now in 2019, so we're bringing it back up the blog for your attention!
Images are an important element of any website; our brains digest them 50x faster than words, and research suggests that the appropriate use of imagery on a website can even increase sales. In fact, one survey has revealed that blog posts and articles containing pictures are 94% more likely to be read through to the end.
That’s because when used effectively, images help to establish an emotional connection between a website and its users. But that’s not the only thing they’re good for. While their main objectives are to add visual appeal and to support and strengthen marketing messages, images can also have a positive impact on your SEO strategy.
So for some useful tips on optimising your images for Google search, keep on reading…
Avoid embedding important text inside images
Any text that is contained within an image cannot be read by search engines or screen readers. That means it is completely inaccessible to some, such as those who are visually impaired, and rely on screen readers to convert the web’s textual content into an audio format. When contained within an image, text is also inaccessible to Google and cannot therefore be used to help increase the website’s visibility in search engines (if you read our most recent post on optimising your web copy for search, you’ll know that the more text there is available to Google on your website, the better it is for SEO!).
In addition, when an image scales down to fit onto mobile phone and tablet screens, so does the text within it, rendering it almost impossible to read. Since it’s likely that a large proportion of your web traffic now comes from mobile devices, it’s really important to ensure the text on your site is easy for those accessing it via small screens to read.
So, in order to provide all users with the best possible experience of your website, and to ensure you get maximum SEO value from your web copy, keep as much of it as you can in regular old HTML.
Name your images appropriately
Since Google is just a robot and cannot visualise or make sense of pictures, it will look to an image’s file name for clues about its subject matter. You can help Google out by assigning relevant, detailed and informative file names, such as “new-red-mercedes.jpg”, which says a lot more about an image’s content than “IMG001.jpg”.
Google will sometimes use this information if it cannot find enough suitable on-page content to display in its search results, so try to get one or two of your most important keywords into the image’s file name if you can.
Take care when formatting file names
Make sure any spaces within your image file names are replaced with hyphens (not underscores). While most CMS’ will translate spaces into a format that browsers can read (“%20”), there are still some that won’t. If yours doesn’t, your images will break, showing your users one of these instead of the image that you intended:
Furthermore, Google has been known to dish out brownie points in the interest of user-friendliness, and “new-red-mercedes.jpg” is much easier to read than “new%20red%20mercedes.jpg”.
Assign alt text
The “alt” attribute on an < img > tag is used to describe an image and, if it has one, its function on the page (e.g. if an image were being used as a call to action button, its alt text should say something along the lines of “click button to buy this product”).
Though you’re not strictly required assign alt text to your images, it’s important that you do so for the following reasons:
• To enhance SEO - In the same way that file names do, alt tags provide Google with useful information that can be used to decide which images to return when a search query is submitted.
• To enhance user experience - Descriptive alt text helps to make images accessible for people who cannot see them, such as those who rely on screen readers, or those with low bandwidth connections.
The best alt attributes will be descriptive and detailed, providing users with relevant and useful information about the image:
Poor alt attributes may be empty, non-descriptive, or stuffed with keywords:
Alt attributes that are stuffed with keywords may be perceived as spam and could actually have an adverse effect on your SEO. So, in order to avoid this, we would just recommend that you focus on creating useful, information-rich alt text that speaks to the end user, and uses keywords only where appropriate and in context.
Make images responsive
We’ve talked a lot about the benefits of responsive web design (RWD) on the MAD4 blog; the bottom line is that with mobile internet usage on the continual incline, RWD can help to improve the experiences of those who access your website via mobile phones and tablets. Google is also a huge fan of RWD, so it's worth doing what you can to get Google on your side!
To maximise the SEO value of your images, you must ensure that they scale down to fit laptop, tablet and mobile phone screens. You’ll find more about optimising your images for small screens here.
If you've read any of the other posts in our recent series of SEO tips, you may have gathered that the main takeaway is pretty much to provide your end user with as much information-rich content as possible, and to focus on a human audience, rather than on ways to manipulate the search engines (as backwards as that might sound!). The same applies here.
The reason being is that Google's main objective is to provide its users with high quality search results that offer useful and relevant information. So, if you're focusing too much on trying to please Google (opposed to the people who will actually be reading your content), you could be wasting your time...
While we are firm believers in SEO through keyword research, we can also safely say that stuffing your image file names and alt tags with keywords (alongside other black-hat SEO tactics) will likely do your website more harm than good. And while there is definite SEO value in implementing the steps we've outlined above, the reason for this is because doing so will help you to add value for a human audience.
With that in mind, the best advice we can give you is to always consider the end user when trying to optimise your website for search. If you have any tips that you feel may be useful for your fellow readers, please feel free to contact us and let us know, or post them in the comments below. Don't forget to check back for our next piece, where we'll be looking at optimising your website's menu/navigation for search.