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Water Intake Calculator

How much fluid do you need on a normal day? Enter your weight and adjust activity and weather — you'll get an instant reference value.

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Your result

Your reference value for daily fluid intake:

2.3 liters

roughly 9 glasses of 250 ml each

Part of this comes naturally from food such as fruit, vegetables or soups — you don't need to drink it all.

How it's calculated

Reference value of around 33 ml per kilogram of body weight, plus allowances for activity (350–700 ml) and hot days (500 ml). For comparison: EFSA states an adequate total water intake for adults of about 2.0 l (women) and 2.5 l (men) per day.

All results are general reference values and are no substitute for medical advice, diagnosis or treatment. If you have health concerns or are unsure, please talk to your doctor.

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