Water is an essential part of a dog’s body and critical to good health. Water is essential for all cellular, organ, and tissue functions of the body. One realizes the importance of water when faced with the negative consequences of dehydration. As little as a 10% loss of body water can be fatal.
Water in the body is not static but a constant and dynamic process. Dogs lose water through breathing, panting, urinating, and having bowel movements. Dogs take in water primarily through drinking water but also get some water from eating food and to a small degree by the body’s normal metabolism.
We refer to this dynamic flow of fluids as “intake” and “output”. Intake is primarily from drinking and water content in food. Output is fluid loss through normal methods of panting, drooling, urine, bowel movements as well as abnormal means such as diarrhea, vomiting, or blood loss.
Dehydration results from more “output” than “intake”. Overhydration results from more “intake” than output.
Factors that Affect How Much a Dog Should Drink
There are factors that can impact how much water a dog should drink. For example:
- Dry dog food vs. canned dog food. Dry dog food has approximately 15 and up to 30% water while canned dog food can contain 50% to 75% water. Dogs that eat canned food may drink and require less water.
- Body weight. Bigger dogs require more water than smaller dogs. Water requirements are based on body weight.
- Sodium. Just as we have increased thirst after ingestion of a high salt snack, ingestion of high sodium foods in dogs can create a need for increased amounts of water intake.
- Exercise & Activity. Dogs that are more active generally drink and require more water.
- Weather Exposure. The high temperatures of the spring and summer generally cause dogs to pant. Panting helps them regulate their body temperature but also is a way they lose water. It is critical for dogs to have access to shade but also plenty of fresh clean water at all times.
- Drug therapy. Some medications may increase a dog’s water intake. Drugs may include steroids or diuretics such as Furosemide (commonly known as Lasix).
- Disease. Some diseases such as kidney disease or Diabetes can cause increased thirst in dogs.
How Much Water Should a Dog Drink?
The amount of water a dog should drink per day is dependent on his size. The general rule is that dogs drink 20 to 40 ml of water per pound of body weight per day. This comes out to about 3 to 4 cups of water for a 20-pound dog.
Below is a table with more details based on size. Note there is a range. Much of the range is determined by the factors listed above. And like people, some dogs are better at drinking water than others. Here’s a chart to help you understand how much water your dog needs based on their weight.
Dogs 3 – 5 pounds
60 to 200 mL/day
¼ to almost a cup
Dogs 6 – 10 pounds
120 mL to 400 mL/day
½ cup to little over 1 ½ cups
Dogs 11 – 20 pounds
220 mL to 800 mL/day
1 cup to 3 1/3 cups
Dogs 21 – 30 pounds
420 mL to 1200 mL/day
1 ¾ cup to 5 cups
Dogs 31 – 40 pounds
620 mL to 1600 mL/day
2 2/3 cups to 6 ½ cups
Dogs 41- 50 pounds
820 mL to 2000 mL/day
3 ½ cups to 9 1/3 cups
Dogs 51 – 60 pounds
1020 mL – 2400 mL/day
4 ¼ cups to 10 cups
Dogs 61 – 70 pounds
1220 mL – 2800 mL/day
5 cups to 11 2/3 cups
Dogs 71- 80 pounds
1420 mL – 3200 mL/day
6 cups to 13 1/3 cup
Dogs 81 – 90 pounds
1620 mL – 3600 mL/day
7 cups to 15 cups
Dogs 91 – 100 pounds
1820 mL – 4000 mL/day
7 ½ cups to 16 2/3 cups
Dogs 101 – 110 pounds
2020 mL – 4400 mL/day
8 2/3 cups to 19 1/3 cups
Dogs 111 – 120 pounds
2220 mL – 4800 mL/day
9 ¼ cups to 20 cups
Dogs 121 – 130 pounds
2420 mL – 5200 mL/day
10 cups to 21 cups
Dogs 131 – 140 pounds
2620 mL – 5600 mL/day
11 cups to 23 1/3 cups
*rounded to the nearest quarter cup
Note: There are 240 mL in a cup, 4 cups in a quart, 8 cups in a half gallon, and 16 cups in a gallon.
What are Water Recommendations for Dogs?
- If your dog is active, he or she is in the heat, or has any fluid loss such as from vomiting and diarrhea, they may require more water than what is listed above.
- It is recommended that you give your dog plenty of fresh clean water at all times.
- Your dog’s water bowl should be washed thoroughly twice weekly and ideally by running through the dishwasher.
- Your dog’s water bowl should be big enough to hold 36 to 48 hours of water.
- Offer one water bowl outside and one inside. If you have multiple dogs, it is recommended to have more than one water bowl in the house.
- Please contact your veterinarian if you have any concerns about your dog’s water intake. Learn more about Why is My Dog Not Drinking Water?
- Not drinking can be dangerous and lead to life-threatening dehydration. Learn more about Dehydration in Dogs.
Additional Articles that May be of Interest About How Much Should a Dog Drink
Does Dog Water Intoxication Exist?
Why is My Dog Not Drinking Water?
Should I Give My Dog Tap Water?
Drinking, Drinking, Drinking – Your Dog and Diabetes
Ideal Daily Schedule for Dogs and Puppies
Excessive Drinking (Excessive Thirst) in Dogs
Why is My Dog Drinking Tons of Water?
Dehydration in Dogs
Why Water is Important
Diabetes in Dogs
Kidney Failure (CRF) in Dogs