About this tool
Estimate how much water you should drink each day from your body weight (about 35 ml per kg) plus an adjustment for exercise time, shown in liters, cups and fluid ounces. It is calculated live in your browser.
Frequently asked questions
How is the recommendation calculated?
It uses a baseline of roughly 35 ml of water per kilogram of body weight, plus about 12 ml for every minute of exercise to replace fluids lost through sweat.
Does food and other drinks count?
This is a guide for total fluid; some of it comes from food and other beverages. Hot weather, illness and pregnancy can all increase your needs.