Water Intake Calculator

Calculate how much water you should drink daily based on your weight, activity level, and climate. Stay properly hydrated with a personalized recommendation.

Daily Water Recommendation

2.8
liters per day
2,800 ml
Milliliters
95 oz
Fluid Ounces
11
Cups (250ml)
Base (weight-based)2,450 ml
Activity addition+350 ml
Climate addition+0 ml

How Water Needs Are Calculated

A common recommendation is 35 ml per kg of body weight as a baseline, adjusted for activity and environment:

Daily Water = (Weight × 35ml) + Activity + Climate

Active people lose more water through sweat and need to replace it. Hot or humid climates increase perspiration and water needs.

About 20% of daily water intake typically comes from food (fruits, vegetables, soups). The rest should come from beverages, primarily water.

Signs of dehydration: dark urine, thirst, fatigue, dizziness, dry mouth. Aim for pale yellow urine as a hydration indicator.

Frequently Asked Questions

The 8×8 rule (eight 8-oz glasses = ~2 liters) is a simple guideline but not based on strong science. Actual needs vary significantly by body size, activity, and climate. This calculator provides a more personalized estimate.

Yes, though rare. Hyponatremia (water intoxication) can occur from drinking extreme amounts quickly. Spread your intake throughout the day and listen to your body.

Yes, caffeinated beverages do contribute to hydration despite mild diuretic effects. The net effect is still hydrating. However, water is the best primary source.

Yes, illness (especially fever, vomiting, diarrhea) increases fluid needs. Drink extra water and consider electrolyte solutions during illness.

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