BMI calculator
Calculate BMI (body mass index) using the WHO formula. Check whether you are underweight, normal, overweight or obese. Free BMI calculator.
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Daily water intake calculator
Calculate the recommended daily amount of water for your body. It accounts for weight, physical activity and ambient conditions.
How we calculate water intake
Base = weight [kg] × 30–35 ml. Add 350–500 ml per hour of activity and 500 ml in high temperatures.
Example: weight 70 kg, moderate activity
Recommended intake: about 2.3–2.8 l of water per day (including water from food).
Frequently asked questions
How much water should I drink per day?
A common guideline is 30–35 ml per kilogram of body weight, so roughly 2–2.5 l for an adult. The exact amount depends on activity, temperature and diet.
Does activity affect water needs?
Yes. Each hour of physical activity increases your needs by about 350–500 ml of water to replace fluid lost through sweat.
Does food count toward fluid intake?
Yes. About 20% of daily fluid comes from food, especially fruit, vegetables and soups. The calculator accounts for total intake.
Should I drink more in hot weather?
Yes. In high temperatures it is worth adding about 500 ml or more, as the body loses extra fluid through sweat to regulate temperature.
Can you drink too much water?
Excessive water intake in a short time can cause hyponatraemia (low sodium). Drink throughout the day in moderate amounts rather than large quantities at once.
Are the calculator results binding?
No. The result is approximate and is not medical advice. Individual fluid needs depend on health, medication and lifestyle — consult a doctor.
Indicative result
Result is approximate and is not medical advice. Individual needs depend on many factors — consult a doctor.
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