Image optimisation has two primary components. The first one is resizing images without compromising quality, and the second one is optimising images for search engines by incorporating relevant keywords.
Why is image optimisation important?
Page speed - Large, unoptimised images can make your website slow and clunky like nothing else. Your users won’t wait around for your website to load, and optimising your images will go a long way toward ensuring that it loads quickly.
User experience - When your website takes forever to load, it doesn’t exactly provide the best experience for your users. Your users expect your site to load quickly. Optimising your images helps to ensure a better user experience and that you meet users' expectations.
SEO - Image optimisation will help to ensure that your images rank in image searches on Google, and it will also be beneficial to the overall SEO of your website. Additionally, page speed plays an important part of Google’s search algorithm, and image optimisation will help you avoid the organic search penalties of having a slow website.
How to optimise the images on your website
#1. Choose the right image file type
When you’ve created an image, you have to choose a file type to save it as. There are many different options to choose from; here are a few of the most common:
JPEG - JPEG's will work for most of the images on your site, with the exception of any images that have a transparent background. JPEG's are ideal because they allow for higher quality images and smaller file sizes, but fall short when it comes to things like logos or line drawings. With JPEGs, some file data may be lost in compression; although, the loss is not typically noticeable.
PNG - When images don’t have a lot of colour, are transparent or have a lot of text, PNG's are ideal. PNG's, however, will require larger file sizes.
GIF - GIF's can compress images into smaller file sizes, much like JPEG's, but the colour range on GIF's is limited, making it a poor choice for most photography. However, GIF's can be great for animation.
TIFF - In terms of quality, TIFF's are king. However, it comes at the cost of size, as they are uncompressed and therefore much larger than other formats.
WebP - WebP is a relatively new image format that offers both smaller file sizes and higher quality than JPEG's.
AVIF - AVIF is a new image format that is similar to WebP but with better compression, meaning it can offer even smaller file sizes at the same level of quality.
#2 Resizing your images
Large images can slow your website down as well as impact on your SEO. And, since most people won’t wait longer than three seconds for a website to load, site speed is of the utmost importance for user experience and google rankings.
As a guide we recommend images stay under 1MB or the max size your site will allow.
#3 Use keywords to name your images
Did you know that Google will actually crawl the file names of your images? Make the names of your images have descriptive text and hold a keyword.
If you leave the default image name — dsc16354473.jpg, for example — it’s a missed SEO opportunity. Instead, if the image is of bridal dress, for example, choose something like white-off-the-shoulder-bridal-dress.jpg.
#4 Always optimise your ALT image tags
Alt image tags tell people who have visual impairments what your images are, and they’re used by search engines to determine ranking in image searches, as well as a website’s organic ranking as a whole.
Here are a few tips to keep in mind when writing your ALT tags:
Use plain, descriptive language in your alt image tags, much like when you renamed the image file
If the image is of a product with a serial number or model number, include it in the alt image tag
Need some SEO help?
If you would like us to help conduct an audit of your website or support you to ascertain where improvements can be made, get in touch with us at hello@sisumarketing.co.uk
Comments