It looks like a baby bullfrog. I keep and breed both regular and albino bullfrogs. I also keep northern green frogs which look similar except they have a ridge on both sides that go all the way down the back. However bullfrogs lack that ridge. They do have a little ridge behind the eyes over the ear. From those pictures I say bullfrog.

Edit to add that bullfrogs also have bigger eyes and a more rounded nose. Most green frogs keep their pattern however a lot of bullfrogs will lose the spots and striped legs as they age. There is no way to tell if your frog will keeps it's pattern or not.

Also I agree that baby is way too skinny. Babies need to eat everyday. Only feed insects that are as wide as the with of the mouth or the space between the eyes.