How Google Identifies and Indexes Images
So what exactly does Google look at when indexing images? This will help to provide a quick review of what Google assesses before digging into how to optimize images.
- Google can index BMP, GIF, JPEG, PNG, WebP, and SVG image files.
- To learn more about a particular image when Google’s algorithms index an image, Google looks at the written copy on the page where the image was found as well as the page’s title and body.
- Google also considers anchor text (the hypertext link) pointing to the image, the image’s filename, and its alt text (descriptive text about the image).
In addition, Google may use other methods and data points such as the caption from the Image Sitemap.