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
Enter your weight, activity level and climate — the calculator returns your recommended daily water intake.
Na tej stronie
How we calculate
Base = 32.5 ml × body weight (kg). Adjusted by activity multiplier (×1.0–1.4) and climate multiplier (×1.0–1.2). Rounded to nearest 50 ml.
Example: 70 kg, moderate activity
For 70 kg with moderate activity in a temperate climate: approx. 2300 ml (2.3 l) per day.
Frequently asked questions
How much water should I drink per day?
General guideline: 30–35 ml per kg of body weight. Activity and heat increase needs significantly.
Does coffee count towards daily water intake?
Yes — caffeinated drinks have mild diuretic effect but still contribute net fluid. Plain water is best.
What are signs of dehydration?
Thirst, dark urine, fatigue, dry mouth, headache. Urine should be pale yellow.
Do I need more water when exercising?
Yes — add 500–1000 ml per hour of moderate exercise, more in heat.
Can I drink too much water?
Yes, overhydration (hyponatremia) is rare but possible. Healthy kidneys can process about 0.8–1 litre per hour.
Do fruits and vegetables count?
Yes — food provides 20–30% of daily water intake. Foods like cucumber, watermelon, lettuce are >90% water.
Does body weight affect water needs?
Yes — larger people need more water. This calculator scales intake with weight.
What about hot climates?
High temperatures and sweating increase needs by 20% or more. Increase intake in summer or hot countries.
Is sparkling water as good as still water?
Yes — sparkling water hydrates equally well. Choose whichever you prefer.
Should athletes drink more?
Yes — very active individuals may need 3–4 litres or more per day. Use sports drinks for sessions over 1 hour.
For informational purposes. Consult a doctor for kidney or heart conditions.
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