Facebook has increased the size of images in link page posts by 4x on mobile and 8x on desktop to help you drive better fan engagement.
To optimize your images for this new format:
- Use images that are 1200 x 630px or greater for the best display on high-resolution devices. At the minimum you should use images that are 600 x 315px to display link page posts with larger images.
- Use images that have an aspect ratio of 1.91:1. Try to keep your images as close to this aspect ratio as possible to avoid any cropping in News Feed.
- Use the og:image tag to choose the image that you want shared when users share your link. If you don’t use the og:image tag, users can choose the image they want to post, giving them a chance to select an image that is poor quality. To do this, add the meta tag to your source page:
<meta property="og:image" content="http://yourimage.png"/>