There is no definitive answer to which dog has the strongest jaw because the bite force (amount of pressure in a dog’s bite) will vary among different animals and according to the circumstances.

There was a study by National Geographic on dogs and wolves, to see which one had the strongest bite. Just for comparison’s sake, humans can bite with 120 pounds of force. A wolf came in with the strongest bite force of 406 pounds. If he is defending himself, his bite force can reach 1200 pounds.
Next are the results of the top three domestic breeds of dogs who are known for their strong jaws and high attack rate on people, putting them on the list of dangerous dogs.
Other dogs thought to have a forceful bite are Dobermans and Mastiffs.
To answer the question, “Which dog breed has the strongest jaw?” in general, it would have to be either a Rottweiler, a Mastiff, or a Doberman.
To know the answer to, “Which dog breed has the strongest jaw?” you need to understand bite force. The size of the dog is not the only factor in bit force. There are several factors that determine the force of a dog’s bite. One is the size of the head. Scientists agree that this in instrumental in determining how much pressure the jaw can exert. It is hard to study a dog’s bite because he will exert different pressure each time he bites. So there can only be general assumptions made about a breed’s bite force.
There is no certain way to determine which dogs are dangerous. A vicious dog is usually one who has attacked in the past, so it’s considered to likely attack again. Of course, stronger dogs with a higher bite force will do a lot more damage if they attack. Some insurance companies deny coverage to people who own Rottweilers, Pit Bulls, German Shepherds, Doberman Pinschers, Huskies, and Chow Chows. Of course, whether or not a dog will attack has a lot to do with training. These dangerous dogs need to be taken proper care of, receive obedience training, and should be socialized at a young age. Just because they have a strong bite force doesn’t mean that they cannot be loyal and friendly companions.
To help your dog be healthy, happy and not a biter, there are several things you should do: