Baseline Hydration Calculator
Calculate your minimum daily fluid requirements based on body mass.
The "8 Glasses" Myth
The advice to "drink 8 glasses of water a day" lacks scientific backing. Hydration needs scale linearly with body mass and vary drastically based on ambient temperature and exertion.
This calculator uses the standard clinical baseline of 30-35ml of fluid per kilogram of body weight for adults under age 65.
Food Contains Water
Remember that about 20% of your daily fluid intake comes from food (fruits, vegetables, soups). You do not necessarily need to drink the entire amount as pure water; coffee, tea, and other fluids contribute to the total.