Dog & Cat Water Intake Calculator
A healthy dog needs roughly 50–60 ml of water per kilogram of body weight a day, and a cat about 40–50 ml — food moisture included. Enter your pet’s weight and we’ll turn that into a daily target in cups, fluid ounces, and millilitres, so you know what normal looks like.
Typical water per day
— cups / day
How to use it
- 1 Pick dog or cat and enter your pet’s weight.
- 2 Read the daily water range and the typical mid-point in cups and ounces.
- 3 Watch for big changes — a sudden jump or drop in drinking is worth a vet call.
Why this matters
Both too little and too much drinking can be early signs of a problem — kidney disease, diabetes, and urinary issues all show up first as a change in thirst, especially in cats. Knowing your pet’s normal daily range makes it far easier to notice when something shifts. The estimate uses the standard veterinary rule of about 50–60 ml/kg/day for dogs and 40–50 ml/kg/day for cats.
Frequently asked questions
How much water should my dog drink a day?
About 50–60 ml per kg of body weight per day, so a 20 kg dog needs roughly 1–1.2 litres (about 4.5–5 cups). Active dogs and hot weather push it higher. Counting both bowl water and moisture in food.
How much water should a cat drink?
Around 40–50 ml per kg per day — about 180–225 ml (¾–1 cup) for a typical 4.5 kg cat. Cats on wet food drink much less from the bowl because their food is ~75% water, which is completely normal.
When is changed drinking a problem?
Drinking a lot more or a lot less than usual — or producing much more urine — can signal kidney disease, diabetes, or a urinary problem. Increased thirst in an older cat especially is worth a vet visit. Use this tool to learn your pet’s baseline so you can spot the change.
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