When it comes to the best image size for SEO, you’ll want to compress the file size but without sacrificing the quality. There are a variety of tools that allow you to compress image files before or after uploading them to your website. Keeping the file sizes smaller is important because it won’t affect your page speed. It is also important to make sure your image is in the correct file format. JPEG is the most popular since you can keep file sizes small. There is also PNG formatting that allows for transparency and higher quality, but the file sizes tend to be a little bit larger.