Images and SEO – Making the most of pictures

Images are powerful stuff, real attention grabbers. But what if a human visitor can’t see very well? And what about search engines? They can’t ‘see’ images at all. They can only decode words: the descriptions and <img> tags we apply to images. 

It’s important to name and code pictures sensibly so people and search engines understand what you’re on about.

Images and SEO – Being accurate and logical

If you call your pictures things like image1.jpg and logo.jpg, you’re missing a trick because the name doesn’t mean anything to human readers or search engines. You need to make it clear to people and bots exactly what the picture’s about: green-tree-frog-on-a-leaf.jpg or bill-smith-and-sons-logo.jpg.

You’d be surprised how often it happens, but you really don’t want to call images weird things like 3Zmmm346T-zz-123.jpg either, again because it’s meaningless.

You can include key terms in your image file name but don’t go mad. Keyword stuffing is a big no-no. Put the needs of your readers first and you can’t go far wrong.

Taking the SEO side of things too far

Imagine you’re creating a page about fairy cakes. It’s cool to call your cake image fairy-cakes.jpg. But calling it buy-cheap-fairy-cake-making-equipment-here.jpg in an attempt to play the system is bad practice. It’s best to say it like it is.

Using hypens in image file names

It’s good to use-hyphens-between-words-in-your-image-file-names because it means search engines can easily recognise the separate words in their own right.  But never leave empty spaces between words and don’t use+plus+or+minus+signs to separate them.    

Image <alt> text

<alt> text is descriptive code used by search engines and people with accessibility issues. Here’s where you can elaborate and get a bit more creative.

Say you have a cartoon of a skinny man in a fat man’s clothes. You could use the <alt> text a skinny man in fat man’s clothing. If the image links to somewhere else you can add more the alt tag reads: skinny man in a fat man’s clothing – click here for our skinny man clothing page. You’re being clear and honest, describing exactly what’s going on to help people who can’t see well and search engine spiders/bots understand your intentions.

You can also use descriptive key phrases in your link anchor text. But again, don’t stuff it with key terms.

Harnessing your CMS

Many content management systems, including WordPress, let you specify alt descriptions, so take full advantage.

Image load speed

Google takes load speed into account, giving fast-loading images preference over fat files that take aeons to load. Billions of people around the world are still stuck with slow dial-up connections and Google takes accessibility very seriously. On the other hand, because poor quality images put visitors off and make you look unprofessional, it’s a case of balancing file size against quality.

As a general rule it’s best to upload actual size images instead of using html code to re-size them, which wastes bandwidth.

Making images relevant

It’s beautiful. It’s an excellent balance of good quality and small file size. You’ve named it accurately and created compelling alt text. But if your image has nothing to do with the content it’s supposed to enhance, it won’t work as hard as it could. Pictures can speak a thousand words… but only when they support the message.

Image SEO checklist

  • find an image that reflects and supports your message accurately and clearly
  • create accurate descriptive file names without keyword stuffing
  • keep your file size as low as possible while retaining quality
  • write an accurate, creative alt-description tag for every image