Is this just plain water?
Total fluid intake includes water from food and other beverages, not just plain water.
Health
Water Intake Calculator
Enter your weight and select your activity level to get a recommended daily water intake.
Live calculator output
Enter your weight and activity level to see your recommendation.
How it works
The calculator multiplies your body weight by an activity factor to estimate daily water needs: Daily Water (ml) = Weight (kg) × Factor, where the factor ranges from 30 ml/kg for sedentary individuals to 45 ml/kg for very active people.
The result accounts for water from all sources including food and beverages. About 20% of daily water intake typically comes from food, so actual drinking water needed is slightly less than the total shown.
Practical example
A 70 kg person with moderate activity: 70 × 35 = 2,450 ml (about 2.5 liters or 10 glasses per day).
A very active person at the same weight: 70 × 45 = 3,150 ml (about 3.2 liters or 13 glasses). In hot weather, add 500–1,000 ml to these estimates to compensate for sweat loss.
Frequently asked questions
Should I drink more in hot weather?
Yes. Heat, humidity, and altitude all increase your fluid needs.
Can I drink too much water?
Rarely, but overhydration is possible. Follow your thirst and these guidelines as a baseline.
Does coffee count toward water intake?
Yes. While caffeine is a mild diuretic, the net hydration from coffee and tea is positive. They count toward your daily fluid total.
How do I know if I am drinking enough?
The best indicator is urine color. Pale straw yellow means well-hydrated. Dark yellow or amber suggests you need to drink more.
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