Dog Water Intake Calculator
See how much water your dog should drink each day, and when it’s too much.
Includes water from food. Dogs on wet food drink less from the bowl.
Typical water per day
4¾–5¾ cups
- Fluid ounces
- 38–46 fl oz
- Milliliters
- 1,130–1,360 mL
- Talk to your vet if it’s regularly over
- 77 fl oz (2,270 mL)
How: 22.7 kg × 50–60 mL = 1,134–1,361 mL. 1 cup = 237 mL.
Always leave fresh water out. Hot weather, exercise, dry food and nursing all raise needs.
Quick answer
Most healthy dogs drink about 50–60 mL of water per kg of body weight a day, or roughly 1 fl oz per pound. A 50 lb dog needs about 4¾–5¾ cups a day. Regularly drinking more than about 100 mL per kg (1.5 fl oz per lb) is a reason to see your vet.
How do I use the dog water intake calculator?
- Enter your dog’s weight in pounds or kilograms.
- Read the daily range in cups, fluid ounces and milliliters.
- Note the vet threshold. If you think your dog drinks more, measure intake for 3 days before you call.
This is for healthy adult dogs at rest in mild weather. It isn’t a target to force; a healthy dog with water available regulates its own intake.
What formula does the water calculator use?
Talk to your vet above = weight in kg × 100 mL
1 US cup = 237 mL · 1 fl oz = 29.6 mL
The 50–60 mL/kg range for healthy dogs and the 100 mL/kg threshold for polydipsia are the figures used in veterinary teaching on excessive thirst (for example, WSAVA congress proceedings and the BMJ journal In Practice). The Merck Veterinary Manual gives a similar general range of about 44–66 mL/kg for mammals in a comfortable environment.
How is the calculation done?
For the default example, a 50 lb dog:
- Convert weight: 50 lb ÷ 2.2046 = 22.68 kg.
- Low end: 22.68 × 50 mL = 1,134 mL.
- High end: 22.68 × 60 mL = 1,361 mL.
- Convert to cups (237 mL each): 4.8–5.8 = 4¾–5¾ cups, or 38–46 fl oz.
- Red-flag line: 100 mL × 22.68 = 2,268 mL (about 77 fl oz). Regularly drinking more than that is worth a vet visit.
Worked example: a 20 lb dog on wet food
A 20 lb (9.1 kg) dog needs about 450–540 mL a day, or 1⅞–2¼ cups. If it eats two 5.5 oz cans of wet food at about 78% moisture, the food already supplies roughly 240 mL. So seeing only about 1½–2 cups disappear from the bowl is normal. Swap to dry kibble and bowl drinking will go up.
How much water does a dog need by weight?
| Weight | Cups | Fl oz | mL | Vet check above |
|---|---|---|---|---|
| 5 lb | ½–⅝ | 4–5 | 110–140 | 8 fl oz |
| 10 lb | 1–1⅛ | 8–9 | 230–270 | 15 fl oz |
| 20 lb | 1⅞–2¼ | 15–18 | 450–540 | 31 fl oz |
| 30 lb | 2⅞–3½ | 23–28 | 680–820 | 46 fl oz |
| 40 lb | 3⅞–4⅝ | 31–37 | 910–1,090 | 61 fl oz |
| 50 lb | 4¾–5¾ | 38–46 | 1,130–1,360 | 77 fl oz |
| 60 lb | 5¾–6⅞ | 46–55 | 1,360–1,630 | 92 fl oz |
| 70 lb | 6¾–8 | 54–64 | 1,590–1,910 | 107 fl oz |
| 80 lb | 7⅝–9¼ | 61–74 | 1,810–2,180 | 123 fl oz |
| 100 lb | 9⅝–11½ | 77–92 | 2,270–2,720 | 153 fl oz |
What makes a dog drink more?
- Heat and humidity. Dogs cool themselves by panting, which loses water.
- Exercise. A long hike or a game of fetch can raise needs a lot.
- Dry food. Kibble is only about 3–11% water.
- Nursing. Lactating dogs need much more water to make milk.
- Salty treats and some medications, such as steroids and diuretics.
When should you see your vet?
- Your dog regularly drinks more than the “vet check” amount for its weight.
- Your dog is peeing much more, having accidents, or asking to go out at night.
- Increased thirst comes with weight loss, appetite change, vomiting or lethargy.
- Your dog won’t drink, or shows signs of dehydration such as sticky gums or sunken eyes. Don’t restrict water while you wait.
Frequently asked questions
How much water should a dog drink a day?
A healthy dog drinks roughly 50–60 mL per kg of body weight a day, which is about 0.8–1 fl oz per pound. A 50 lb dog needs about 4¾–5¾ cups a day. Heat, exercise and dry food push that up.
How much water is too much for a dog?
Vets usually call it excessive thirst (polydipsia) when a dog regularly drinks more than about 100 mL per kg a day. That’s roughly 1.5 fl oz per pound. It can be a sign of kidney disease, diabetes or hormone problems, so book a vet visit.
Does wet food count as water?
Yes. Canned food is usually 60–87% water, so dogs on wet food often drink noticeably less from the bowl. That’s normal. The totals in the calculator include water from food.
How can I measure how much my dog drinks?
Fill the bowl with a measured amount in the morning, top up with measured amounts, and subtract what’s left 24 hours later. Do it for 3 days and average, since daily intake varies.
Should I limit my dog’s water at night?
For healthy adult dogs, no. Always leave fresh water available. For puppies in house training, some trainers lift the bowl an hour or two before bed; ask your vet if that’s right for your puppy.
Why is my dog not drinking water?
Cool weather, wet food and low activity can all lower thirst. But if your dog drinks very little for a day, seems lethargic, or has vomiting or diarrhea, call your vet; dogs can dehydrate quickly.
Sources
- Merck Veterinary Manual. Nutritional Requirements of Small Animals: water (most mammals need about 44–66 mL/kg/day; canned food moisture 60–87%). merckvetmanual.com
- WSAVA 2011 Congress (VIN). Approach to the dog with polyuria and polydipsia: healthy dogs 50–60 mL/kg/day; polydipsia over 100 mL/kg/day. vin.com
- Diagnostic approach to polyuria and polydipsia in dogs. In Practice (BMJ), 2019. doi.org
- Merck Veterinary Manual. Diabetes Insipidus in Animals (measuring water intake at home). merckvetmanual.com
Vet disclaimer: These are estimates for healthy pets. Your vet knows your pet. Ask them before changing diet or care, especially for puppies, kittens, seniors, pregnant pets or pets with health conditions. Read our medical disclaimer.