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Water Intake Calculator

Estimate recommended daily water hydration in liters, ounces, and glasses based on weight, activity, and climate.

Body & Activity

Daily Water Intake

2.8 L

≈ 11.7 standard glasses (8 oz / 240 ml) or 95 fl oz

Base Need

2.5 L

Exercise

+0.4 L

Climate

+0 L

Estimate only — not medical adviceView details

Hydration needs vary based on medical conditions, kidney health, fever, and medications. Consume water steadily throughout the day rather than all at once.

How it works

The Water Intake Calculator estimates your daily hydration target by combining baseline physiological needs with adjustments for physical exercise and climate conditions.

The baseline calculation uses the established guideline of approximately 35 milliliters of water per kilogram of body weight (about 0.5 ounces per pound).

Adds approximately 350 ml of hydration for every 30 minutes of moderate or intense cardiovascular exercise.

Factors in environmental sweat loss during hot, humid summer days or dry winter conditions.

Frequently asked questions

Does coffee or tea count toward daily water intake?
Yes. While caffeine has a mild diuretic effect in non-habitual consumers, modern research confirms that coffee, tea, and moisture-rich foods (fruits and vegetables) contribute to overall daily hydration.
How do I know if I am sufficiently hydrated?
Urine color is the simplest indicator: pale straw or light yellow indicates good hydration. Dark yellow or amber indicates you should drink more water.
Can you drink too much water?
Yes. Drinking excessive quantities in a short period can cause hyponatremia (water intoxication), diluting blood sodium levels. Sip water steadily throughout the day.

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