Water Intake Calculator

How much water to drink each day for your weight, exercise and weather — in litres and glasses, with a simple schedule.

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30 kg150 kg
0 min180 min
150 ml500 ml
Drink about—

A simple schedule

    Water intake calculator

    Staying well hydrated helps your energy, concentration, digestion and kidneys — and in Indian summers it can prevent heat exhaustion. This water intake calculator estimates how much water you need each day from yourbody weight, your exercise and the weather, and turns it into a number of glasses with an easy schedule so the target doesn't feel like a chore.

    How to use it

    1. Enter your weight and how long you exercise on a typical day.
    2. Tick hot weather if it applies.
    3. Follow the schedule, and drink a little extra whenever you feel thirsty.

    Example

    A 65 kg person who walks for 30 minutes on a hot day needs about 65 × 35 ml = 2.3 litres, plus 0.5 litres for the exercise and 0.5 litres for the heat — about 3.3 litres, or 14 glasses of 250 ml. Spreading this through the day works better than drinking a lot at once. Track your activity with thesteps to km converter and your calories with thecalorie calculator.

    Health disclaimer: This tool gives general estimates for information only and is not medical advice, diagnosis or treatment. Please consult a qualified doctor about your health. Read the full disclaimer.

    Frequently asked questions

    How much water should I drink a day?
    A common guide is about 35 ml per kg of body weight — around 2.5 litres for a 70 kg adult — plus extra for exercise and hot weather. Food (fruit, dal, curd, vegetables) provides some water too. Thirst and pale-yellow urine are good everyday signs that you’re drinking enough.
    Do I need more water in Indian summers?
    Yes. Heat and humidity increase sweating a lot, especially outdoors. Add at least half a litre on hot days, more if you work outside, and include salt and electrolytes (nimbu pani, buttermilk, ORS) if you sweat heavily.
    Do tea and coffee count?
    Mostly, yes — the water in tea and coffee counts towards your intake, though very strong or sugary drinks are best limited. Plain water, buttermilk and coconut water are excellent choices.
    Can I drink too much water?
    Yes. Drinking several litres in a short time can dangerously lower sodium in the blood. People with kidney, heart or liver conditions may need to restrict fluids — follow your doctor’s advice rather than this calculator.

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