Water Intake Calculator

How much water to drink per day based on weight and activity.

Per day
2.7 L
Cups (240 ml)
11

Guide: ~33 ml per kg of body weight + ~350 ml per 30 min of exercise.

Important: This calculator is for general information only and is not a medical diagnosis or advice. All calculations run in your browser — nothing is sent or stored.

Frequently asked questions

How much water should I drink a day?

A guide is about 30–35 ml per kilogram of body weight, plus extra for exercise and hot weather. This calculator uses ~33 ml/kg plus an activity top-up.

Do coffee and tea count?

Yes, most drinks contribute to fluid intake, though water is the best choice. Water-rich foods (fruit, soups) also help.

Can too much water be harmful?

Rarely, drinking a very large amount in a short time can dilute blood sodium (hyponatremia). Stick to the guideline amounts unless a doctor advises otherwise.

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