Water Intake Calculator — How Much Water Should I Drink?
Fluid needs rise with body size, exercise and heat — and much of Pakistan is very hot for months of the year.
Updated
For general information only — not medical advice. Consult a doctor or registered dietitian before making health decisions.
Formula
Base = 33 ml × Body weight (kg)
+ 350 ml per 30 minutes of exercise
+ 500 ml in hot weather
This is a practical rule of thumb. Thirst and pale-yellow urine are good everyday guides.
Examples
70 kg, 30 min exercise, hot weather
Aim for about 3.2 litres of water a day
55 kg, no exercise, mild weather
Aim for about 1.8 litres of water a day
Important information
- During Ramadan, spread water intake between iftar and sehri rather than drinking a lot at once.
- Outdoor workers in summer may need much more; include oral rehydration salts (ORS) when sweating heavily.
- These results are general estimates for healthy adults and are not medical advice. Children, pregnant or breastfeeding women, athletes and people with medical conditions should seek professional guidance.
Frequently asked questions
How much water should I drink a day?
Many adults need roughly 2–3 litres of fluids a day, more in heat or with exercise.
Do tea and other drinks count?
Yes, most drinks count toward fluid intake, as does water in food.
Can you drink too much water?
Yes, very large amounts in a short time can be dangerous. Spread intake through the day.
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