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.

Yes — sparkling water hydrates equally well. Choose whichever you prefer.

Yes — very active individuals may need 3–4 litres or more per day. Use sports drinks for sessions over 1 hour.

Calculator · Health

Enter your weight, activity level and climate — the calculator returns your recommended daily water intake.

Shareable result: your inputs are saved in the page address.

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.

For 70 kg with moderate activity in a temperate climate: approx. 2300 ml (2.3 l) per day.

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.

Indicative result

For informational purposes. Consult a doctor for kidney or heart conditions.

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