Daily Water for Pet by Weight

Daily water intake for dogs and cats

A healthy adult dog drinks about 60 ml of water per kg of body weight per day. For a cat the figure sits closer to 50 ml/kg/day. That puts a 20 kg dog at roughly 1.2 L/day and a 4 kg cat at around 200 ml/day. Heat, exercise and lactation can push intake up by 50% or more, which is why fresh water should always be within reach. Pets eating dry kibble drink 2–3 times more water than pets on wet food, since canned food is roughly 75% water and already covers a big chunk of the daily fluid. Cats are famously bad drinkers, and they tend to do better with a running fountain and a few bowls kept well away from where they eat.

Applications

Daily water targets show up in pet nutrition planning and in dehydration prevention, especially during summer and after surgery. They matter for chronic kidney disease (CKD) management, which is extremely common in older cats, and for diabetes monitoring, where sudden polydipsia is a red flag. The same numbers help pet hotels and kennels run their day and let you size automatic fountains and water dispensers properly.

FAQ

My pet drinks much more than the calculated value — should I worry? If intake stays above 100 ml/kg/day (polydipsia) for a while, that can point to kidney disease, diabetes or hyperthyroidism. Book a vet visit.

Wet food vs dry food — same target? No. With wet food, the meal itself supplies around 60–70% of the daily fluid, so the water you actually see your pet drink drops a lot. That's normal and healthy.

How can I get my cat to drink more? A running fountain usually helps. Spread a few bowls around the house, keep them away from the litter box and the food, and go for ceramic or stainless steel rather than plastic. Working some wet food into the diet makes a real difference too.