What is the best size for OG images?
According to Facebook, the minimum size should be no less than 1200×630.
Example
Here is what a 1200×630 px image looks like when shared on Facebook. According to many articles on the Internet, this is a good general purpose OG image size which will display your post, article, or product listing page properly on the major social networks.

How to make an OG Image
- Go to your favourite graphics editor such as Photoshop, Affinity Designer, Photopea, or Canva for example, and create a new 1200×630 px document.
- Place your image to fit into the canvas.
- Export your image as a png or jpg.
When exporting, keep the file size small like under 300kb for example. Keeping file sizes small is best practice to ensure faster loading of images into browsers.