How can air weigh so much? It is all air pressure. As you might know, the Earth is covered with a blanket of gases. That is called the atmosphere. The air from the atmosphere takes up space, so it has mass (weight). The more atmosphere above you, the more the air pressure. There is actually 14.7 pounds per square inch of your body pushing down on you right now!! You can’t really feel the air pressure because your body is pushing outward, the opposite direction of the air pressure. That is why the air in an average room can weigh over 100 pounds!