What Breed is My Puppy?
My dog looked similar to yours when he was a puppy. The shape of the face makes me think he has a little (very little) boxer. Also, his colorings and fur make me think he is also mix with both German Shepherd and Chow.
What Breed is My Dog?
The broad chest and legs are definite signs that it is an American Bull Dog. It is not a boxer (people often confuse the two)