To tell if a dog is dangerous, look for the following signs: Growling: Dogs tend to growl when they’re angry or scared. It’s their way of warning the person who is causing them to feel that way. Clenching, baring, or showing teeth: This happens when the dog feels stressed, threatened, confused, or intimidated; it’s typically a sign that they are about to attack. Snarling: This is a combination of showing teeth and growling. Dogs typically snarl when there’s an impending attack. Lunging: This is either an attempt to scare or attack you. It’s usually preceded by a snarl, growling, barking, or teeth-clenching. Becoming still while growling: This is also referred to as “freezing.” If you see this, it means an attack is imminent and you need to stay away from the dog or immediately stop whatever you’re doing to the dog. Sprinting aggressively towards you or the target: When a dog dashes aggressively at you or someone else, it’s likely going to attack. Eye contact: If a dog approaches you, becomes still, and stares directly at you, it is likely about to attack.