Ditto is a small, child like size humanoid alien. He has white skin, and a black head with black shoulders. Ditto’s hands are large with 4 digits and his feet are merely stubs. He has 3 fins on his head. Ditto also has gem-like circle on his arms and 3 craters on his waist.
Ditto wore the Omnitrix symbol on his forehead in the original series. Ditto now wears the Ultimatrix symbol on his chest in Ultimate Alien.
Ditto has the ability to clone himself without limit. Unlike Echo Echo, every clone operates independently on their own mind, regardless whether the others wants them to and each clone is indistinguishable from the others. Ditto and his clones are all linked, which allows them to share each other’s physical pain. Ditto can also breathe underwater.
Ditto's clones share a physical link with each other, making it so that when one clone is hurt, all other clones feel the same pain. This means if one clone is killed, the others are automatically killed as well, thus meaning the ability to form an army of clones can not happen.