To make sure your profile picture looks good on all devices, test it on different phones, tablets, and computers. Ensure important details are not cropped and the image remains clear and legible even at smaller sizes.
For the profile picture on Instagram, it is recommended to use a size of 110 x 110 pixels. However, note that the image should be square to avoid distortion. Instagram will automatically scale the image to display it, but make sure it’s uploaded at the recommended size.
The answer to that depends on the type of Instagram account you have. If you have a personal account, it’s advisable to use your face as your profile picture as it creates a personal connection with your followers. If you represent a company or brand, it may make more sense to use your logo to reinforce brand identity.