And why image tags are essential for SEO in 2020

“A picture paints a thousand words.”

How many times have you heard that in your lifetime? It may be an old worn-out English adage but when it comes to websites and SEO, as maxims go its pure gold. You should write it on a large sheet of paper and pin it above your computer screen as a permanent reminder.

We all know the importance of using images in your web pages:

  • They help illustrate a point or concept
  • They make the page more engaging for readers
  • They can communicate more effectively than words alone

And when it comes to page rankings in search engines, if images rule then image tagging is the power behind the throne.

Human beings like pictures. Research shows that 59% of people think visual information is more important than text. Search marketers have known about the power of images for a long time and it seems search engine users know it too. Image-based searches are taking an increasingly large slice of search requests with 62% of millennials and “Generation Z” saying they would rather use visual search than anything else.

Example of a typical Google search result for “Dog Breeds” shows image results as well as page results

And nobody wants to look at a webpage that’s nothing but text. Even if you have lots of interesting things to say, a screen full of text runs the risk of being boring and your site visitors won’t hang around long enough to read your shiny pearls of wisdom.

So you need to break the text up with relevant images (which can be photos, illustrations, infographics, etc) that help to tell your story and keep your readers interested. But images also need to be optimised with the correct tags otherwise you may as well not bother with them at all.

Why do you need to tag your images?

The problem is that while search engines like to see you using images, they can’t read what’s in them so they can’t tell whether they are pertinent to the user’s search or not. Even images that have embedded or overlaid text are invisible to search engines – unless they are also correctly tagged.

An example of text embedded in an image which can’t be read by search engines or screen readers

So you must tag your images with useful descriptions of their contents. It’s unavoidable if you want any chance of being ranked higher than your competitors. Search engines will see this as good SEO practice. Plus it will keep you compliant with the Equalities Act, meaning you’re making your site accessible to those with a visual impairment. Anyone who uses a screen reader needs to know what’s in the image. You therefore need to add a useful description to help them understand your content better.

Additionally, image tagging is important to provide contextual relevance about the page where the image resides. When you tag your images properly, it gives your site a ranking boost because the tags are a helpful relevance signal for search engines. Plus search engines will give preference to websites that provide a better user experience for their visitors.

And last but not least, because a search engine will read all your image tags, you have a golden opportunity to use your keywords. This means that if your images are described correctly and contain relevant keywords, they will end up at the top of searches for that type of product or service.

Little boy trying to squeeze through a hole in a fence

The impact of optimised image tagging – a real-life example

During the course of our work we review dozens of websites and we’re constantly surprised by how many website owners do not tag their images, or if they do the tags don’t contain optimised or useful descriptions. It’s a simple task to create tags as you upload an image to your site’s media library and the difference it makes to your page rankings could be remarkable.

Recently we spent some time going through the images on a website and creating SEO friendly and keyword-rich image tags. We made no other major changes to the site but within a week we saw the page impressions (the number of times the website appeared in search results) jump by over 100% – more than doubling its search engine visibility:

Google Analytics screen shot showing how image tagging improved total impressions for a website

Just from adding useful image tags!

So what are your options when it comes to optimising your images?

Various types of image tagging

Image tags are variously called Alt Text, Alt Tags or Alt Attributes. But the only two key terms you need to know are:

  • Alt Text
  • Image Title Element

Depending on the design platform you are using these tags may be labelled differently, but they perform the same functions. The Alt Text is what visually impaired people hear from their screen readers so it should describe what’s in the picture.

The Image Title Element is what’s displayed if an image doesn’t download (for example if a user automatically suppresses images for faster download speeds) and so should communicate how the image supports the surrounding text. It’s also what gets displayed as a bubble or caption when you hover over the image:

An example of an Image Title Element which shows when images are blocked and when you hover over an image

Although technically the two descriptions can be identical, they each perform a different function so SEO best practice is to make them different – and tags should never ever be duplicated anyway.

Image file names need optimising too

There is a third image tag you need to pay attention to: the image file name.

Another common mistake we see website owners making is to assume that the image file name is only seen by them and is just for internal reference. As long as they know what the image is, that’s all that matters. So they leave their images labelled as “Image123.jpg” or something equally generic when they upload them.

Wrong! The image file name is the first thing search engines read. It gives them the first clue to what the image is about and how relevant it is to the search. So if you have an image with the file name “Image123.jpg” which is actually of a brown leather bag with buckles, then you should rename the image file as “brown leather bag with buckles”.

Hint: Image file names are just as searchable as any other type of tag.

How to write image tags

All three types of image tags are a perfect opportunity to use your keywords. The best image tags are short descriptions of about 100-125 characters in a grammatically correct sentence that makes sense when reading out loud.

How to write Alt Text descriptions

Alt Text is mainly for screen readers so you need it to be as descriptive as possible, communicating what’s in the picture and containing at least one of your keywords. Let’s use this photo as an example:-

red Manolo Blahnik stilleto shoes with Prague in background

An e-commerce site would not want this picture of a pair of shoes to have Alt Text simply reading “Red shoes.” You would instead want to enter: “Woman wearing red Manolo Blahnik satin pumps with three-inch stiletto heel and diamante trim with bridge in the background”. This phrase falls well under 125 characters, but it is much more descriptive and gives anyone using a screen reader a reasonable idea of what’s in the picture.

Hint: Don’t start Alt Text with “Picture of…” or “Image of…”. Screen readers already know from the HTML source code that it’s a picture and you’ll be using up valuable character space. Jump right into the image description and try to be as vivid as possible to bring it to life.

How to write Image Title element descriptions

You need the Image Title element to describe not just what’s in the image, but also how the image relates to the surrounding text. Using the shoe example above, the Image Title element description could read: “Red classic Manolo Blahnik women’s satin pumps in a wide range of sizes perfect for weddings, parties or special celebrations”.

Again this fits within the 125-character limit and communicates not just a description of the product but how the product may be used.

How to write an image file name

Image file names can be much simpler and focus on describing the subject matter. Using our red shoes example one last time, this particular image file name reads: “Manolo Blahnik red shoes”

Hint: All image tags should be written with the user in mind. Do not focus purely on SEO and search engines. Try to be as natural as possible, providing information that reads well, makes sense and supports the context of the subject matter.

We hope we’ve given you a good idea of the importance of proper image tagging and the positive impact it can have on your search engine page rankings. For more information about SEO best practice and to arrange a free 30-minute consultation, please get in touch.

Author bio:

Helen Say is the co-owner of CBL Copywriting and SEO. She is an experienced copywriter and is passionate about de-mystifying SEO for small business owners. She also wishes she made enough money from copywriting to invest in a pair of Manolo Blahniks from time to time.