Steve’s SEO tips Myth #14
Images do not require any optimization
Google uses both URLs and file names to understand images, making optimization a necessary part of the discoverability process. Let’s start with the basics.
When it comes to image formats supported by Google, stick to the following: BMP, GIF, JPEG, PNG, WebP, and SVG.
As for the alt text, this serves a couple of purposes. For one, alt text makes your images accessible for those who can’t see them. It also helps Google understand the image — and should be optimized to do just that. This doesn’t mean stuffing a bunch of keywords into the alt text, but rather writing a descriptive filename that clearly states what the image is displaying. Think: “vanilla ice cream cone with rainbow sprinkles” vs. “ice cream.”
To further optimize images for discoverability within the Image Search results, consider an Image sitemap. This will give Google more information about your images and help the search engine discover images it might not crawl otherwise. Additionally, you’ll want to use semantic HTML markup — <img> or <picture> — to help Google process your images, as CSS images are not indexed.
Finally, let’s touch on image compression. Google rewards pages with faster page speed and places those that lag lower on its rankings. So, it’s important to make sure your page-load times are as quick as possible. One of the leading culprits of page lag is large photos. If the photo you uploaded is too big, it will make the page take a longer time to load — even if the image doesn’t seem huge on-screen.
Once you pick a photo, use free compression software, like Squoosh.app to make it as small as it can go before it loses any quality. Any removal of excess photo data will speed up loading times so readers won’t have to wait.