We often think of dogs as indomitable and durable animals who can fend off attackers, tirelessly chase Frisbees, and even eat poop without digestive consequences.
It’s true that dogs generally have a solid constitution, but that shouldn’t lead you to believe they can endure one of the biggest mistakes a pet owner can make: Leaving them in a hot car—even for a few minutes—puts a dog’s life at serious risk.
The Dangers of Leaving Your Dog in a Hot Car
Even on relatively cool days with temperatures around 71.6°F, the inside of a vehicle can reach 116.6°F within an hour, as Quartz highlights.
If it’s a scorching summer heat wave, an 80-degree day will see temperatures get up to 99°F in just 10 minutes; a 90-degree day can turn the car into an oven at 119°F in the same amount of time.
Dogs can’t tolerate this kind of heat. As their bodies struggle to cool down, the temperature is often more than they can expel through panting and opening capillaries in the skin. If their body reaches a temperature of 105.8°F, they’re at risk of heatstroke, which only half of dogs survive. At 111.2°F, a lack of blood circulation can cause kidney failure and internal bleeding. Brain damage and death is very likely at this point. Depending on the outside temperature, it can happen in as little as six minutes. Cracking windows won’t help. Unless you plan on leaving your vehicle running with the air conditioning on (and we don’t recommend that), there’s really no safe amount of time to leave a pet inside.
What to Do If You Find a Dog Trapped in a Hot Car
If find a listless dog who is unresponsive, it’s best to get to a veterinarian as soon as possible. And if you’re a bystander who sees a dog trapped inside a car, alert the nearest store to try and make an announcement to get the owner back to the vehicle.
You can also phone local law enforcement or animal control. In some states, including California, you’re legally allowed to enter a vehicle to rescue a distressed animal. If local law enforcement instructs you to remove the dog from the vehicle, be sure to check for any unlocked doors. If you have to break a window, choose one that's least likely to shatter glass onto the trapped pup. You should also have some sort of plan for how to secure and handle the dog after you rescue it—according to to the American Kennel Club, a belt or purse strap could serve as a makeshift leash.
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A version of this story originally ran in 2018; it has been updated for 2025.