Estimate how much water to drink daily based on your body weight and exercise duration.
Hydration needs vary with climate, health status, diet, activity and other factors. This is a general educational estimate, not medical advice.
The calculator provides a general daily water estimate based on body weight and an exercise-time adjustment. It is intended as a starting point, not a medical prescription.
Example
Actual fluid needs vary with climate, diet, activity intensity, sweating, illness and other individual factors. Thirst, urine color and professional guidance may also help inform hydration decisions.
Is "eight glasses a day" actually a real rule?
Not really — it's more of an easy-to-remember myth than a hard science number. Your real need scales with body weight and how much you sweat during exercise, which is exactly what this calculator factors in instead of a flat one-size-fits-all number.
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