How does WPSSO Core find and select images?

The images used in the Open Graph, Rich Pin, Twitter Card meta tags and Schema markup are chosen in this sequence:

1. Video preview image(s), when the “Include Preview Images” option is checked under the “Edit Media” tab in the Document SSO metabox.
2. A custom image selected under the “Edit Media” tab in the Document SSO metabox.
3. An e-commerce product image from a supported 3rd-party plugin like Easy Digital Downloads or WooCommerce (Premium edition).
4. A featured or attached image from the WordPress Media Library.
5. Image(s) from <img/> HTML tags in the content text.

Most of these methods will lead to a properly sized image with correct dimensions since the image ID can be determined (provided the original image is large enough).

Always upload the largest images you can to the Media Library and let WordPress create the resized / smaller versions as required. If an original image is smaller than the required image dimensions, it will be ignored / rejected – so always upload the largest images possible.

To satisfy the recommended Facebook image size of 1200x630px and Google’s required 1:1 image size of 1200x1200px, you should always make sure to upload images that are larger than 1200x1200px.

See why you shouldn’t upload small images to the Media library.