Health
Hydration needs depend on body size, climate, exercise, pregnancy, and health conditions. General ml-per-kg heuristics offer a starting point for otherwise healthy adults.
Hydration needs depend on body size, climate, exercise, pregnancy, and health conditions. General ml-per-kg heuristics offer a starting point for otherwise healthy adults.
Thirst, urine color, and clinician guidance remain important signals. Over-hydration can be dangerous in rare medical contexts.
CalculatorCamp water intake tool provides rough daily volume guidance, not prescription fluid orders for hospital or renal patients.
Enter weight and activity or climate options if available. Calculate to see suggested daily water intake in liters or cups.
This water intake calculator applies the standard relationship below. Intermediate values are kept at full precision; only the displayed result is rounded.
common heuristic: ~30–35 ml per kg body weight; adjust up for exercise/heat
A 70 kg person with moderate activity: base 70 × 35 ml = 2450 ml, plus 500 ml for activity = 2950 ml, or about 2.95 L per day — roughly 12 glasses of 250 ml. Hot weather, illness, or pregnancy can raise the need.
Most healthy adults count them toward fluid intake in moderation.
Excessive intake can dilute sodium; follow medical limits if you have heart/kidney disease.
No. General educational estimate.
Yes.
The factors and formulas used by this tool follow these references:
Health and fitness results are estimates for general education and planning. They are not medical advice and do not replace an assessment by a doctor, registered dietitian, or other qualified professional.
Last reviewed: September 2026. Found an error? Tell us and we will correct it.
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