What does this tool do?
Fluid needs rise with body size, sweat losses and heat. This calculator starts with a weight-based baseline, adds an exercise allowance, then applies a modest climate adjustment.
The Formula
Fluid (ml) = (Weight × 35 + Exercise minutes × 12) × Climate factorFrequently Asked Questions
Does food count toward fluid intake?
Yes. Food, coffee, tea and other drinks contribute fluid. The target is a planning guide for total fluid, not a requirement to drink only water.
Can drinking too much be harmful?
Yes. Very large amounts in a short time can dilute blood sodium. Spread intake across the day, and follow medical advice if you have heart or kidney conditions.