Water Intake Calculator
Find your optimal daily water intake.
About this tool
The Water Intake Calculator estimates your daily hydration target in cups, ounces, and litres based on your body weight, activity level, and climate. Proper hydration supports energy, concentration, and physical performance.
How it works
- Enter your weight (in kg or lb).
- Select your activity level and whether you live in a hot climate.
- Click Calculate to see your recommended daily intake.
- Track your intake against the target throughout the day.
Example use cases
- Active individual: A 180 lb person who exercises moderately has a recommended intake of approximately 3.0-3.5 litres (roughly 12-14 cups) per day.
- Sedentary adult: A 130 lb sedentary adult in a temperate climate needs approximately 1.9-2.2 litres (8-9 cups) per day.
Frequently asked questions
Does coffee or tea count toward daily water intake?
Yes - caffeinated drinks do contribute to hydration, though they have a mild diuretic effect. Plain water, herbal tea, and water-rich foods also count.
Can I drink too much water?
Yes - hyponatremia (over-hydration) is possible, particularly for endurance athletes. The calculator targets the appropriate range for most healthy adults.