Recommended daily water
Calculate how much water you should drink daily by weight and activity.
"8 glasses a day" doesn't fit everyone. Calculate your real hydration need in liters and glasses.
By VOV · Last updated: October 21, 2026
How it works
How it works: base of 35 ml per kilo of body weight, adjusted by activity (sedentary ×1, moderate +0.5 L, intense +1 L). A general guide for healthy adults in mild climate; heat, illness or pregnancy raise the need.
Frequently asked questions
Does coffee count as water?
Partially: it hydrates despite being mildly diuretic. But don't replace water; count at most half your intake.
Can you drink too much water?
Yes, though rare: over 1 liter per hour for many hours can cause hyponatremia. Drink to thirst and with sense.
What if I train in the heat?
Add 0.5-1 L per hour of intense exercise and consider electrolyte drinks if you sweat a lot.