BuddyPress.org

BuddyPress creates two images for avatars. 150×150 and 50×50. Any other sizes you see are scaled by CSS.

If you really know what you are doing, you can define these with custom values in wp-config.php to change the real sizes of the files that are created, but I am not sure of any side effect that may occur.

define( ‘BP_AVATAR_THUMB_WIDTH’, 50 );

define( ‘BP_AVATAR_THUMB_HEIGHT’, 50 );

define( ‘BP_AVATAR_FULL_WIDTH’, 150 );

define( ‘BP_AVATAR_FULL_HEIGHT’, 150 );

If you are going to do this make sure you test extensively on a sandbox install first!