Water Intake Calculator
Estimate how much water you should drink each day.
Quick answer
A common baseline is about 30–35 ml of water per kilogram of body weight per day (roughly half your weight in pounds, in ounces), adjusted up for heat and exercise. Thirst and pale-yellow urine are practical everyday guides.
Suggested daily water
2.7 L
≈ 90 fl oz
Glasses (250 ml)
11
From food (typical)
~20% of needs
Where the number comes from
A common baseline is ~33 ml per kg of body weight, plus roughly 350 ml per half hour of exercise. Adequate-intake guidelines (3.7 L/day men, 2.7 L women, all fluids including food) land in the same territory for average adults.
Thirst is a good sensor
For healthy people, drinking to thirst plus pale-yellow urine is a reliable target — the precise liter count matters less than avoiding sustained deficit. Heat, altitude, pregnancy, and illness all raise needs; kidney or heart conditions need medical guidance instead of formulas.
Frequently asked questions
- How does the Water Intake Calculator work?
- A common baseline is about 30–35 ml of water per kilogram of body weight per day (roughly half your weight in pounds, in ounces), adjusted up for heat and exercise. Thirst and pale-yellow urine are practical everyday guides.
- Is the Water Intake Calculator free to use?
- Yes. The Water Intake Calculator is completely free, runs entirely in your browser, and requires no account or sign-up. Your inputs never leave your device.
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