How to Optimise Images for SEO
Optimising a website focuses primarily on improving the content, and developing the meta information located on the search pages of a search engine such as Google. However a lot can be said for optimising the images as well, having engaging images which are relevant to the content, improves the viewing pleasure of a website. Below is demonstrated a useful guide of things to keep in mind when optimising images for your website.
Tags and Titles
The title of the image should reflect what you want the user to associate your image with. For example, if you image is of a cactus, but you title the image with ‘plant’ it’s doesn’t specifically describe what the reader is seeing. The same can be said for the alt-tag. This means alternative text, and signifies to Google what is contained in your image.
It’s never a bad idea to also include a keyword in the alt-tag. On this note, try not to overuse keywords. This is largely because after a certain amount of characters (around 150) Google stops listening. Using a keyword within an alt-tag signifies that it is important as you have used an image to demonstrate it. This will help to add relevance and improve the probability of you getting highly ranked within search engines for that keyword.
Underscores are also disregarded, for example ‘Hedgehog-cactus.jpg’. Using a hyphen splits up the words, however if it was to be written as Hedgehog_cactus.jpg’ it would be read as hedgehogcactus.jpg, making it more difficult for search engines, for example Google, to understand.
File size and quality is important to any website, not only do you want the images on your site to be visually appealing, but you want them to have a positive effect, and not slow down the time it takes your website to load. If a potential customer was to visit your website and, despite it being a fantastic website, it took over 15 seconds to load, chances are, no one will wait that long to see it. However, if your website took 1-2 seconds, Google will assume that this is a reputable website as it runs more smoothly, therefore increasing your chances of ranking higher within the search engine.
It is probably common sense that the larger an image is, the longer it takes to load, however sometimes scaling down the size of the image – depending how you do this – can affect the quality of the picture. Always save files as a .jpg, rather than for example as .Gif as it is known for having the best quality as well as the smallest file size.
If you are adamant on having a very large picture on your website (i.e. Over 70kb) then it may be a good idea to use a thumbnail of that image, linking to the larger image with the URL, thus decreasing the waiting time for the website to load. According to Amazon, slowing the page time by just one second would lose the company $1.6billion a year in profit...definitely a good incentive to make sure your website runs quickly!
A few other things to keep in mind:
- Having the option to share an image on social media i.e Facebook, Twitter or LinkedIn, is a positive idea as although it may not contribute to SEO it does endorse the content of the image, thus making it more appealing.
- Using an authorship image in your Google search result window also helps your web page to stand out.
- If using a thumbnail, it will need to have a different file name to the full size image it is linking to, so as to avoid duplication of content, and decreasing the risk of the thumb-nailed image being indexed, as opposed to the larger one.