Daily Water Intake Calculator
Find how much water to drink a day, in litres and glasses, based on your weight and exercise.
These are example values. Enter your own.
Result
This is a general guide. People with kidney or heart problems should follow their doctor’s advice on fluids.
How it's calculated
A common guide is about 33 ml of water for every kg of body weight, plus about 350 ml for every 30 minutes of exercise. Formula: water (ml) = 33 × weight (kg) + 350 × (exercise minutes ÷ 30). One glass is counted as 250 ml. Example: a person who weighs 70 kg and exercises for 30 minutes needs about 33 × 70 + 350 = 2,660 ml, or 2.66 litres a day. That is about 10 to 11 glasses. Without exercise, a 50 kg person needs about 1.65 litres (7 glasses), 60 kg about 2 litres (8 glasses), 70 kg about 2.3 litres (9 glasses), 80 kg about 2.65 litres (11 glasses) and 90 kg about 2.95 litres (12 glasses). You need more water in hot weather, especially in Pakistan’s summer when temperatures go above 40°C, and also during fever, illness or breastfeeding. Pale yellow urine is a good sign that you are drinking enough.
Frequently asked questions
How much water should I drink a day?
Most adults need about 2 to 3 litres a day. A common guide is 33 ml per kg of body weight, plus about 350 ml for every 30 minutes of exercise. Enter your weight above for your own number.
How many glasses of water should I drink per day?
Most adults need about 8 to 12 glasses of 250 ml a day, depending on weight and activity.
Is this calculator free and private?
Yes. It is free to use and needs no sign-up. All calculations run in your browser, so the numbers you enter are not sent to our server.
How many litres of water should I drink daily?
About 2 to 3 litres for most adults. Heavier and more active people need more, and everyone needs more in hot weather.
How much water should a man drink a day?
Men usually weigh more than women, so they often need more water. An 80 kg man needs about 2.65 litres a day before exercise.
Does drinking water help with weight loss?
Water has no calories, so drinking water instead of sugary drinks cuts calories. A glass of water before meals may also help you feel full sooner.
Can I drink too much water?
Yes. Drinking a very large amount in a short time can lower the salt level in your blood, which can be dangerous. Spread your water through the day. Results are estimates for information only, not professional advice.
Results are estimates for information only, not professional advice. · Last updated:
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