Free tool by Omelo
How much water should your dog or cat drink? Enter their weight to get the normal daily range and the thirst level that means it is time to see a vet.
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are we checking?
Select your pet type to get started.
Quick answer: how much water is normal
A healthy dog drinks about 50 to 60 ml of water per kg of body weight each day, and a cat about 40 to 60 ml per kg. So a 10 kg dog needs roughly 500 to 600 ml a day, and a 4 kg cat about 160 to 240 ml. Drinking more than 100 ml per kg per day is excessive (polydipsia) and warrants a vet check, because it can be an early sign of kidney disease, diabetes, or Cushing's disease.
How this calculator works
This calculator uses the daily maintenance water requirement recommended in veterinary references: roughly 50 to 60 ml of water per kilogram of body weight per day. It multiplies your pet's weight by the low and high ends of that range to give a normal daily range in millilitres, then converts to US cups at 240 ml per cup. For cats we show a slightly lower floor of 40 ml/kg, because cats fed wet food take in a large share of their water from food.
The red-flag line is set at 100 ml per kg per day. Sustained intake above that level is defined as polydipsia (excessive thirst) and is a reason to see a vet, whatever your pet's size.
When thirst is a warning sign
A sudden, lasting increase in drinking is one of the most common early signs owners notice before a diagnosis. It is worth acting on even if the total stays under the 100 ml/kg line.
Excessive thirst (polydipsia) can point to kidney disease, diabetes mellitus, or Cushing's disease (hyperadrenocorticism), and is often paired with more frequent or larger urination.
To measure at home, fill the bowl with a known amount, top it up over 24 hours, and note the total. Do this for two or three days. Bring the number to your vet.
Normal reasons for more drinking include hot weather, exercise, a switch to dry food, and nursing. These raise intake without signalling illness.
Why tracking water matters
A single reading tells you little. A trend tells you a lot. Because a rising thirst curve is often the first visible sign of kidney or metabolic disease, logging it over time is one of the simplest early-warning habits an owner can build. Omelo lets you log daily water, see the trend, and get a vet-reviewed read on whether it needs a visit. The calculator tells you where normal sits. Tracking tells you if your pet is drifting away from it.
Frequently asked questions
How much water should my dog drink per day?
A healthy dog needs roughly 50 to 60 ml of water per kg of body weight per day. A 10 kg dog needs about 500 to 600 ml, a little over 2 cups. Puppies, hot weather, exercise, and dry kibble all raise the amount.
How much water should my cat drink per day?
A cat needs roughly 40 to 60 ml of water per kg of body weight per day. A 4 kg cat needs about 160 to 240 ml, close to 1 cup. Cats on wet food drink less from the bowl because their food already supplies water.
How much water is too much for a dog or cat?
Drinking more than 100 ml per kg of body weight per day is considered excessive thirst, called polydipsia, and warrants a vet check. For a 10 kg dog that is more than about 1,000 ml a day. Excessive thirst can signal kidney disease, diabetes, or Cushing's disease.
Why is my pet suddenly drinking a lot of water?
A sudden, sustained increase in thirst is a common early sign of kidney disease, diabetes, Cushing's disease, or a urinary infection. Measure your pet's intake over 24 hours and see a vet if it stays high or the change is abrupt.
Does wet food count toward water intake?
Yes. Canned and wet food is about 70 to 80 percent water, so pets on a wet diet drink noticeably less from the bowl. Both the water in food and the water they drink count toward the daily total.
Source: Maintenance water requirement (roughly 50 to 60 ml/kg/day) and the definition of polydipsia (intake over 100 ml/kg/day) are drawn from the MSD Veterinary Manual (Merck Veterinary Manual). This tool gives general estimates and does not replace veterinary diagnosis.