Instagram post sizes (feed photos):

• Landscape: 1080 x 566 pixels
• Portrait: 1080 x 1350 pixels
• Square: 1080 x 1080 pixels
• Supported aspect ratios: Anywhere between 1.91:1 and 4:5
• Recommended image size: Width of 1080 pixels, height between 566 and 1350 pixels (depending on whether the image is landscape or portrait)