Discover your personalized daily hydration goal based on your body weight, activity level, and climate. Proper hydration boosts energy, focus, metabolism, and overall health.
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Simple strategies to hit your water goals every day.
Drink 500 ml of water immediately upon waking. Your body is dehydrated after 7–8 hours of sleep. This also jumpstarts metabolism by up to 30% for 90 minutes.
Studies show drinking 500 ml 30 minutes before meals reduces caloric intake by an average of 13% and improves satiety signals — a free weight management tool.
Pale yellow urine = well hydrated. Dark yellow = drink more. Clear = possibly over-hydrated. This is your built-in hydration monitor, always available.
Water is the most essential nutrient — more critical than food in short-term survival. Yet most people are chronically mildly dehydrated, which impacts cognitive performance by up to 10%, physical performance by up to 20%, and energy levels significantly.
The standard "8 glasses a day" rule is an oversimplification. Your actual needs depend on body size, muscle mass, activity level, temperature, humidity, and even diet. This calculator uses a weight-based formula (35ml/kg/day) adjusted for these personal factors.
Common hydration questions answered.
A good baseline is 35 ml per kg of body weight. A 70 kg person needs about 2.45 litres daily, adjusted upward for exercise, heat, and other factors. Our calculator personalizes this for you.
Yes, despite mild diuretic effects, coffee and tea do contribute to net fluid intake. However, their diuretic effect means they count for slightly less — we add a small adjustment in the calculation.
Dark yellow urine, fatigue, headaches, dry mouth, reduced concentration, and dizziness are common signs. Note that thirst is actually a late-stage indicator — you should drink before feeling thirsty.
Yes. Add approximately 500–750 ml for every 30–45 minutes of moderate exercise. In hot weather or for intense sessions, this can rise to 1 litre per 30 minutes. Monitor urine colour as a guide.
Overhydration (hyponatremia) is rare and primarily affects endurance athletes who drink excessive plain water without electrolytes. For most people, following the calculated recommendation and drinking to thirst is perfectly safe.
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