srcset — the attribute for image size optimization
Page load speed directly affects the number of users that will read through your article and the experience these users will get from interacting with it. One of the most important factors affecting the page load speed is the size of images.
We use the
srcsetattribute to optimize image sizes. This attribute receives multiple versions of an image in various sizes. Thus, the reader will automatically get the image that fits the size of his screen. E.g., small images for mobile and full-size images for desktop devices.
Your site should generate several sizes of the same image to implement this technology. WordPress generates several sizes by default. Additional sizes can also be generated with theme settings and other plugins.
You can select sizes that will be available on the post page in the Setka Editor plugin settings. To keep image proportions, we only show sizes with the
crop=falsesetting activated. The original image size is on by default.
Screenshot of Setka Editor plugin settings in WordPress: srcset sizes
Please note that WordPress will not generate the image if its' size exceeds the content width of your theme, even if you select it in the Setka Editor plugin settings. You can fix it by changing the content width of your theme.