The pin size recommended by Pinterest is 1000 px x 1500 px. This is an aspect ratio of 2:3.
If you wish to use a different size than the recommended size, we recommend going with one of these options::
Long size: 1000 px X 2100 px
Square size: 1000 px X 1000 px
Video Pin Sizes
Follow these guidelines for video pin sizes:
Recommended: 2:3 aspect ratio
Recommended long: 9:16 aspect ratio
Mid-length: 1:2 aspect ratio
Square: 1:1 aspect ratio
If you stray from these image sizes then you run the risk of your pins having some part of the image cropped which is especially an issue for pins that contain text.