How long can a dog last with no water?

Dogs can survive for several days without food, but only a few days without water. The exact amount of time a dog can survive without water will vary depending on the size, age, and activity level of the dog, as well as the environmental conditions. For example, a large, active dog in a hot environment will need more water than a small, inactive dog in a cold environment. On an average, dogs can last up to 3 days without water.