The optimized image size for photos is 1080px by 1080px. As a result, the aspect ratio is 1:1.
The recommended horizontal image size is 1080px by 566px. The aspect ratio is 1.9:1, but you can also use 16:9.
The recommended Instagram image size for a vertical or portrait photo is 1080px by 1350px while the aspect ratio is 4:5.
Instagram profile picture size
Instagram story size
Instagram video size