// Free tool
Daily water intake calculator
Work out how much water to drink each day — from your body weight, how much you move, and the climate you live in. No sign-up, nothing stored.
This is a general estimate, not medical advice. Your real needs change with health conditions, pregnancy, medication, and altitude — check with a doctor for a personal target.
// The method
How the number is worked out
The estimate starts from your body weight — roughly 33 ml of water per kilogram, which lands in the commonly cited 30–35 ml/kg range for healthy adults.
It then adds about 350 ml for every 30 minutes of exercise to cover what you lose through sweat, and nudges the total up in hot or humid weather. The result is rounded to a practical, easy-to-track figure.
What changes your needs
Movement
The more you sweat, the more you replace. Exercise, physical work, and long walks all add up.
Climate
Heat and humidity raise water loss. Altitude and dry indoor air do too.
Body & diet
Body size, pregnancy or breastfeeding, and water-rich foods all shift the target.
// FAQ
Common questions
How much water should I drink a day?
For most healthy adults it's roughly 2–3 litres from all sources, but it depends on your weight, activity, and climate. The calculator above gives you a personal starting point.
Does coffee or tea count?
Yes. Despite the myth, moderate caffeinated drinks still hydrate you. Water-rich foods like fruit and soup count toward your total too.
Can I drink too much water?
It's rare, but drinking far more than you need in a short time can dilute your blood sodium. Spread your intake across the day rather than forcing large amounts at once.
How do I actually hit my target?
Splitting it into small, regular glasses is far easier than remembering on your own. Hydrame does exactly that — it turns your target into gentle reminders and tracks each glass.