As humans, we know to be careful in extreme temperatures. Unfortunately, our dogs often don’t realize they need to slow down until it’s too late — so it’s on us to protect them from excessive heat. So, how hot is too hot for dogs?
Quick answer: For most dogs, vets recommend caution above 80°F, and by 90°F outside time should be limited to quick potty breaks. High humidity, and the risk factors below, can make things dangerous even faster.
Here’s everything you need to know to keep your dog safe this summer.
Which Dogs Are Most at Risk of Overheating?
The safe temperature isn’t the same for every dog. Certain traits make some dogs much more susceptible to overheating:
- Thick double coats (Huskies, Newfoundlands)
- Brachycephalic (short-nosed) breeds like Pugs and English Bulldogs
- Age — puppies and senior dogs regulate temperature less efficiently
- Weight — overweight or obese dogs overheat more easily (check your dog’s body condition score here)
- Chronic illness — ask your vet if your dog’s condition affects heat tolerance
Dogs in any of these categories need extra caution — especially if they fall into more than one (think: an overweight Pug, or a Husky puppy). If you’re not sure where your dog falls, your vet is the best resource.
Why Dogs Overheat Faster Than We Do
Unlike humans, dogs can’t sweat to cool down. They rely mainly on panting, which cools them through evaporation — but it’s far less efficient than sweating.
Because dogs depend on evaporative cooling, humidity matters just as much as temperature. When the air is already full of moisture, evaporation slows down, and dogs overheat faster than the thermometer alone would suggest.
So, How Hot Is Too Hot for Dogs?
The veterinary consensus:
- Above 80°F — exercise caution, especially with high humidity
- Above 90°F — dangerous for most dogs; limit outdoor time to quick potty breaks
Add in high humidity or any of the risk factors above, and these thresholds can turn dangerous much faster than expected.
How to Keep Your Dog Cool and Entertained Indoors
When it’s too hot for much outdoor activity, these low-effort, high-reward ideas keep dogs cool and mentally satisfied:
- Treasure hunt — hide toys or treats around the house for your dog to sniff out
- Frozen stuffed toys (Kong, Toppl, Yogipot) — fill with peanut butter or other lickable treats, then freeze for a cool, long-lasting puzzle. First time trying one? Start it just cool (not frozen) so your dog learns the game before it gets harder.
- Shredding boxes — for dogs who don’t eat non-food items, hide a treat or toy in a box and encourage them to tear it open. Actively guide the game so they don’t decide every box is fair game for destruction.
- Trick training — a few minutes of mental stimulation tires dogs out fast. Here are some fun tutorials to get started.
- Swimming — a great way to stay active and cool; just provide fresh water and don’t overdo it.
- Early morning or late evening walks — take advantage of cooler temps and softer sun.
Signs of Overheating in Dogs
(Source: PetSafe)
Early signs (heat stress)
- Heavier, faster panting than usual
- Increased thirst, seeking out water
- Seeking shade or lying on cool floors
- Slower pace or lagging on walks
- Slightly darker or brighter pink gums
Moderate signs (heat exhaustion)
- Thick, ropey drool
- Bright red gums and tongue
- Weakness or wobbly walking
- Rapid heart rate
- Restlessness or reluctance to move
- Vomiting or diarrhea, sometimes with blood
Emergency signs (heat stroke)
- Disorientation, stumbling, or collapse
- Gums turning pale, gray, purple, or bluish
- Tremors or seizures
- Loss of consciousness
- Not responding to their name
- Extreme lethargy or inability to stand
Knowing how hot is too hot for dogs is one of the simplest ways to prevent a summer emergency.
Heat stroke is a medical emergency. If you suspect your dog is experiencing it, get them to an emergency vet immediately.
Common FAQs
How hot is too hot for dogs? Vets generally recommend caution above 80°F and avoiding extended outdoor activity above 90°F, especially in humid conditions.
Can dogs get heatstroke without being in direct sun? Yes. Humidity slows the evaporative cooling dogs rely on when panting, so they can overheat even in shade or indoors without airflow.
Which dogs are most at risk of overheating? Dogs with thick double coats, short-nosed (brachycephalic) breeds, puppies, seniors, overweight dogs, and dogs with chronic illness are all at higher risk — especially if more than one factor applies.
What should I do if my dog shows signs of heat stroke? Treat it as an emergency and get your dog to a vet immediately. Don’t wait to see if symptoms improve on their own.
Interested in enrolling your dog at School for Dogs? Learn more about our training services here.