The weather is warming up and you may be having some concerns about your dog. One big question is how long a dog can go without water?
Today we’re talking about what’s normal for a dog’s water intake and what happens in extreme cases.

Summertime is here and there are lots of concerns about keeping our dogs safe!
Knowing how hot is too hot for dogs and hot to keep them hydrated or the two biggest concerns with the hot weather.
Maybe you are worried about your dog at home while you are at work, or found a stray who may need some help.
So how do you know how long your dog can last without water?
Every dog is different and therefore will have different water needs.
However, there are some general guidelines you can follow to ensure your pup stays healthy and hydrated.
In today’s post, we’ll discuss how long a dog can go without water under various conditions, as well as what you can do to ensure your furry friend stays properly hydrated.
How Much Water Does a Dog Need?
The general rule of thumb is that a dog should drink about one ounce of water per pound of body weight per day.
For example, a 15-pound dog would need to drink about 15 ounces of water every day.
However, this is just a general guideline; some dogs may need more or less water depending on various factors, such as activity level, climate, health conditions, etc.
Size Matters
When it comes to how long a dog can go without water, size really does matter.
Smaller dogs have a higher surface area to body ratio than larger dogs, which means they lose water faster.
They also have a higher metabolism, which means they require more water to maintain their body functions.
For these reasons, small dogs can only go without water for about 12 hours before they start to show signs of dehydration.
Larger dogs have a lower surface area to body ratio and a slower metabolism than smaller dogs, which means they don’t lose water as quickly.
Additionally, they have more stored body fat that helps insulate them and keeps them hydrated for longer periods of time.
Most large dogs can go without water for 24 hours before showing any signs of dehydration.
However, it’s important to keep in mind that these are general guidelines and that individual dogs may have different needs.
For example, if your large dog is working in hot conditions or exercising strenuously, they may need more water than usual to avoid becoming dehydrated.
Indoors vs. Outdoors
Another important factor to consider is whether your dog is indoors or outdoors.
Dogs who are outdoors in warm weather will need access to water more frequently than those who are indoors or in cooler weather since they will be losing water through panting and sweating.
If your dog is outdoors in hot weather with no access to shade or water, they may only last for an hour or two before becoming dehydrated.
Dogs who are kept indoors in cooler conditions will be able to go for longer periods of time without becoming dehydrated since they won’t be losing as much water through panting and sweating.
Additionally, indoor dogs typically have easier access to water than outdoor dogs since most people keep bowls of fresh water inside their homes for their pets.
In most cases, for dogs indoors, even if you forget to fill up their water bowl in the morning, they’ll likely be fine for the remainder of the day.
How Long Can a Dog Go Without Water?
A healthy dog could generally go without water for about three days before becoming severely dehydrated, but will start to show signs of dehydration within the first 24 hours.
Being able to survive three days without water is only under ideal conditions, such as moderate weather and low activity levels.
If the weather is hot or your dog is exerting himself more than usual (e.g., playing fetch), he’ll like become severely dehydrated much sooner.
Signs of Dehydration in Dogs
If you are worried your dog may be dehydrated, there are several warning signs to look for.
Common signs of a dehydrated dog include:
- Excessive panting
- Lethargy
- Dry nose or gums
- Sunken eyes
- Low urine production
- Low skin elasticity
If you notice any of these signs in your dog, it’s important to take them to the vet immediately.
Ways to Make Sure Your Dog Stays Hydrated
The best way to prevent dehydration in your dog is to make sure they have access to clean, fresh water at all times.
This means filling up your dog’s water bowl regularly and bringing a bowl of water with you when you travel with them.
If you’re going on a long hike or taking them to the beach, bring extra water specifically for your dog.
If your dog is nauseated or vomiting and refusing water, take them to the vet asap.
They may need IV fluids to help hydrate them during illness.
Conclusion
Ensuring your dog stays properly hydrated is vital to his health and well-being.
By following these general guidelines you can help keep your furry friend healthy and hydrated no matter what the weather or activity levels are like.
If you have any concerns about your dog’s hydration levels, be sure to consult with your veterinarian for more specific advice.