Water Intake Calculator
A common planning estimate is about 35 milliliters of water per kilogram of body weight. Climate, exercise, pregnancy, and medical conditions change needs. Thirst, urine color, and clinician guidance still matter more than any single formula.
Estimated water2,450 mL/day
Liters2.45 L/day
US cups (approx.)10.2 cups
Not medical advice.
Formula
Water (mL) ≈ body weight (kg) × 35.
How to use this calculator
- Enter weight in kilograms.
- Read milliliters, liters, and cups.
- Increase on hot or high-exercise days.
Examples
70 kg adult
70 × 35 = 2,450 mL, about 2.5 liters.
FAQ
Is 8 glasses a day required?+
Eight 8-oz glasses is a mnemonic, not a scientific requirement. Needs scale with size and activity.
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