After logging in, you can change your pixiv profile picture by clicking on Profile Image from Profile below the profile image on your page. You can upload a maximum of 3 profile pictures.
You can also upload animated GIF images for your profile after registering as a pixiv premium member.
* Maximum allowed profile image size is 5MB/image.
Supported image formats for upload are JPG, PNG and GIF.
* In the case of animated GIF, a maximum of 20 frames all formatted to the same display size is allowed.
* Animated GIFs wherein the display size changes between frames is not allowed.