kg
Pregnant or Breastfeeding
Adds recommended extra fluid intake
Hydration Tips & Guide
Staying well hydrated improves energy, focus, skin health, and digestion. Most people underdrink without realising it — use these strategies to stay on top of your intake.
Start with a Glass
Drink a full glass of water immediately after waking up. Your body is mildly dehydrated after 6–8 hours without fluids, and this habit jump-starts hydration for the day.
Carry a Reusable Bottle
Having water within arm's reach is the single most effective hydration habit. Choose a bottle with volume markings so you can track intake without thinking about it.
Eat Water-Rich Foods
Fruits and vegetables like cucumber, watermelon, and celery are 90–96% water. Eating them contributes meaningfully to your daily fluid intake alongside what you drink.
General guidance is about 35 ml per kg of body weight — roughly 2.5 litres for a 70 kg adult at moderate activity in a temperate climate. However, your exact needs depend on body size, exercise, climate, diet, and health status. This calculator factors in activity and climate to give you a personalised estimate.
Caffeinated beverages like coffee and tea do contribute to fluid intake. The mild diuretic effect of caffeine doesn't negate the fluid they provide — research shows they are nearly as hydrating as water. However, water, herbal teas, and water-rich foods are still the best primary sources.
Yes — overhydration (hyponatremia) occurs when sodium levels become dangerously diluted, typically from drinking extreme volumes very quickly. For everyday activity, this is rare. The kidneys can process about 0.8–1 litre per hour. Stick to sipping consistently throughout the day rather than drinking large amounts at once.
The easiest check is urine colour: pale straw yellow means well hydrated, dark yellow or amber signals dehydration. Other signs include headaches, difficulty concentrating, dry mouth, low energy, and dizziness. Thirst is already a late signal — don't wait until you're thirsty.