Water Intake Calculator
A daily water intake estimate based on your body weight, exercise, and climate.
Last updated
Educational tool, not medical advice. Actual needs vary by individual, diet, and health conditions. See our terms for details.
—Liters/day
—Fl oz/day
—Cups/day (8 fl oz)
—Glasses/day (250 mL)
About this estimate
The baseline is a commonly cited rule of thumb — about 35 mL per kg of body weight — plus roughly 12 mL for every minute of exercise (in the range of the 350–700 mL per 30–60 minutes often recommended for moderate activity), plus a flat 500 mL if you're in a hot or humid climate where sweat losses run higher. This includes water from food and other drinks, not just what you drink from a glass, and it's a starting point, not a target to hit exactly every day.
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