I refer a lot of people to my SEO 101 page for help with learning the basics of Search Engine Optimization, and I get a lot of questions about SEO in general. But one thing I notice a lot when I’m on websites is that many people don’t seem to realize that their images should be optimized for the search engines as well. And if your website images aren’t search engine-friendly, you are missing out on great opportunities to get noticed by them and improve your site’s overall SEO results. So here are a list of five things you should know about SEO for Images.
File Names Your image file name should be relevant to the content of the photo itself. Since the search engine bots cannot “see” what is in the photo, the file name that you give it should indicate what is in the photo. So, for example, if your image is that of a blue box, then name your photo blue-box. A jpg image with that file name would look like this: blue-box.jpg. And if blue box is one of your keywords, all the better, because keywords in file names is a very good idea. Notice there’s a hyphen too between ‘blue’ and ‘box.’ That is the preferred means of separating keywords in file names. And avoid using stop words (the, she, a, an etc), long file names (shorter file names are always best), numbers, and special characters (other than hyphens).
Alt Text Alt Text is simply an extra way to describe the image in words for the search engines. It should be used, whenever possible, for product photos and any other important photos on your website. If the photos are not important, like images used for decorating or formatting the page, then blank alt text is the preferred way to go. Be sure to think about keywords when writing your alt text, and limit the alt text to under 150 characters, including spaces.
File Size The file size of your image is not its length or width, rather, it’s the size in bytes. If you right-click an image on your computer (or on the Web) to view its Properties, it will display its file size. Where the search engines are concerned, smaller file sizes are best. I have always encouraged people to keep their file sizes at or below 30K. With a good image optimization program, you can achieve outstanding image quality even in small file sizes, so invest in one of those if you don’t already have one. You can find some of my recommendations for these on my Graphics and Photo Tools page. Large photo file sizes will not only affect you negatively with the search engines, but also with potential customers. Why? Large file sizes take longer to load, and the more photos you have, the longer it takes, and the slower your website becomes. People with slower Internet connections will end up frustrated waiting for your site to load if it has a lot of images, and that can make them leave your website. So keeping your file sizes in check is very important.
Page Content The images you use on a web page should relate to the content on that page. So, for example, if you have a page where you are selling sweaters, and there is a photo of a car on the page, what exactly is the relevance? You want your photos to relate to the content of the page.
Hotlinking Also known as remote linking, this is something you should always avoid doing. Hotlinking is where you don’t have a photo uploaded to your own website, rather, it’s on someone else’s website and you are just linking to it in order to make it visible on your own. There are a couple of problems with this. First, you have no control over the file size of that image–it could be huge and take forever to load. Or it could get deleted at some point and you end up with a big red X or broken link on your page. Second, there’s no way to guarantee that the image is a secure object. What if the object is infected with malware? Then your site becomes linked to an infected website! The consequences of that can be that either your website shows in the SERP’s with a warning to anyone who clicks on it that the site may harm their computer, or, your site can be removed from the SERP’s all together! So hotlinking should be avoided whenever possible.
I hope these points have given you some food for SEO thought where you website images are concerned. There are many do’s and don’ts to be considered there. If SEO is your goal, they are all things you should consider while trying to optimize your website.