How Much Water Should You Drink per Day
A common estimate is 30 mL per kg of body weight. A 60 kg adult needs about 1800 mL/day from drinks. Japan's guideline cites about 1.2 L/day from beverages (about 2.5 L total including food).
Open the interactive Everyday Lifestyle tool →Formula: mL = 30 x weight (kg)
Key facts
| Formula | mL = 30 x weight (kg) |
|---|---|
| 60 kg adult | 1800 mL/day |
| Beverage guideline | ~1.2 L/day |
| Total incl. food | ~2.5 L/day |
| During exercise | ~500 mL/h |
Frequently asked questions
How much water for a 60 kg person?
About 1800 mL/day using 30 mL per kg (60 x 30 = 1800 mL).
Does exercise change the amount?
Yes. Add about 500 mL per hour of exercise, up to ~1 L/h in heat above 30 C.
Is 2 liters a day a fixed rule?
No. Needs vary by weight, activity, climate, and diet; the 30 mL/kg estimate is a rough guide.
Related pages
The calculations on this page are estimates based on common general-purpose formulas. They are not medical advice -- consult a doctor or other qualified professional for decisions about your health.
Daily Water Intake Calculator is part of Everyday Lifestyle on GOAT Lab — a free reference you can use without signing up, and it works offline. Open the tool above for any custom value.
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