[Publish] Image resizing

Services and limits

Buffer Publish currently resizes images for the following social networks, checking if the image is too big for the network it's going to be published to, as detailed below:

  • Twitter: 3MB
  • Facebook: 4MB
  • LinkedIn: 10MB
  • Google+: 36MB
  • Pinterest: 10MB

Please note, the image sizes listed above are specifically for third-party apps such as Buffer. When posting natively to these social networks, you may be able to include larger images. For example, Twitter's native image size limit is 15MB.

If the image is over the specified limit, Buffer will convert it to a smaller resolution to make sure we're able to publish it to that network. The original aspect ratio will be kept; we'll adjust one image attribute (width or height) and the other will scale automatically. Images will be transformed to:

  • Twitter: 1024px wide
  • Facebook: 3000px tall
  • LinkedIn pages: 4746px wide
  • Google+: 2048px wide
  • Pinterest: 600px wide
  • Instagram: 2160px wide

Sharing images to Linkedin profiles works a bit differently in that all images will be shared at the dimensions 800x800, regardless of the original image height and width. If sharing to LinkedIn profiles, we suggest using a square image to ensure your image is not cropped.

For Twitter specifically, if the image does not need to be resized, Buffer will still check that the image is smaller than 8192 x 8192px, since that is Twitter's maximum allowed dimension. If it's bigger than that, Buffer will resize it to be just a little smaller than this limit.

If the image is still too big after resizing it within the limits above, Buffer will try to resize it further to ensure it can be published. In this case, it will be resized to 1024px wide, with the height scaling automatically to keep the aspect ratio.

Please note, Buffer Publish cannot currently resize GIF files.