Image SEO Fundamentals
I love doing SEO with images, because it has an artistic aspect and not a lot of people are doing it.
And remember, in big cities like here in San Francisco, people do look for businesses via images, too.
So, it’s time to talk about this!
Like onpage optimization of your website, images have different levels of optimization: the visible layer, the meta layer and the image layer itself. Search engines like Bing and Google have become better and better in image recognition through artificial intelligence and machine learning, but are not yet able to read all image content exactly. For this reason, the context in which the image material is embedded and the meta elements are very important for image optimization.
Image SEO Aspects
- File size: To make it faster and easier for Googlebot to crawl an image url or file into the index, it is recommended to work with moderate file sizes optimized for the web. Thus, for example, no high-resolution outdoor shots with more than 10 megabytes should be used for SEO images. At the same time, the file size of the image has an important influence on the page speed of a web page. Since the loading speed of a website is one of the ranking factors, the optimization of image file sizes is therefore very important.
- File name: This plays an important role for the later ranking in the image search. It should represent exactly what can be seen in the picture. At the same time, the image with the file name is placed in the overall context of a web page. For Google and other search engines, the name offers an important orientation to capture the topic of the website.
- Image size: In SEO circles it is agreed that images that are too small, such as thumbnails or previews, do not stand a good chance of being ranked in the image search. A reference size of 300 pixels has been established for at least one side of the image.
- Image format: When displaying images in the image search, images in landscape format, or more precisely 4:3 format, are usually clicked on more frequently.
- Image source: The URL of the image also plays a role in the images SEO. It is recommended to use a thematically relevant folder structure.
If you want to promote the indexing of image files, you can also store all image URLs in a separate XML sitemap and upload them to the Google Search Console, formerly Google Webmastertools.
- Content: The content around the images is important for the ranking of individual images. The use of relevant keywords plays a major role here.
- ALT attribute: The classic function of the Alt attribute is to describe an image when it cannot be displayed in the browser due to technical problems. Accordingly, the alt attribute should exactly reflect the content of the image and should contain the main keyword.
- Title tag or image title: The meta title should also be used to store a relevant keyword. However, the title is primarily important for improving usability and less than a large SEO factor.
- Markups: With the help of schema.org and other markup languages, images can be provided with structured data that search engines can read. This data makes it easier for the bots to crawl and assign.
Linking with Images
If you link an image to a target website, you need to consider the following aspects for it to be effective!
- Strong internal linking: This can be done either “hard” or indirectly via thumbnails. However, action should also be taken in moderation here.
- Multiple use: In this case, images SEO behaves complementary to content SEO. The multiple use of an image with the same meta data is rather conducive to the ranking. This also applies to exact copies.
- Backlinks: These do not directly affect the ranking. Nevertheless, the more trust a website has, the more likely it is that its images will also rank well.
It is certainly also important in image optimization that the later ranking for a certain keyword or group also depends on the competition. It will therefore be more difficult to rank a celebrity’s name well with the image than with a photo optimized for a fantasy name. It is also conceivable, however, that so-called “longtail” keywords have better chances for good rankings than individual keywords in the image search.
That’s all for this post. We’ll talk more about image SEO soon! 😉