Water Intake Calculator
Calculate your daily water intake needs based on weight, activity level, and climate
Daily Recommendation
3,263 ml
13.6
cups (240 ml)
6.5
500 ml bottles
Based on 35 ml/kg body weight adjusted for activity and climate. Includes water from all beverages and food.
Water Intake Calculator
Calculate your daily water intake recommendation based on body weight, activity level, and climate. Staying properly hydrated improves energy, focus, and physical performance.
FAQ
How much water should I drink per day?
The general baseline is 35ml per kg of bodyweight. An 80kg person needs about 2.8L/day. Add more for exercise (500–750ml per hour of activity) and hot weather.
Does coffee count toward water intake?
Yes — despite being a mild diuretic, research shows caffeinated drinks contribute to daily fluid intake. However, plain water is still the best hydration source.
What are signs of dehydration?
Dark yellow urine, thirst, headache, fatigue, and poor concentration. By the time you feel thirsty, you're already mildly dehydrated.
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