๐งWater Intake Calculator
Estimate your daily water needs from your body weight and activity level. Works in metric or imperial units โ see results in litres, millilitres, cups, or fluid ounces.
This tool provides a general estimate and is not medical advice. Hydration needs vary with health, climate, activity, pregnancy, and individual factors. Consult a physician if you have any condition affecting your fluid intake or any health concerns.
Free Water Intake Calculator Online
Not sure how much water to drink each day? Our free Water Intake Calculator gives you a personalised estimate the moment you enter your details. As a fast and simple water intake calculator, it bases your daily target on your body weight and adjusts it for how active you are โ so you get a figure that fits you rather than a generic "eight glasses" rule.
But it does more than one number. Work in metric or imperial units and see your estimate in litres, millilitres, cups, or fluid ounces, with a higher target on more active days when you lose more fluid through sweat. It also explains that hydration needs vary with climate, health, and individual factors, so you can treat the result as a helpful guide.
Simply enter your weight and activity level to see your estimate instantly. No sign-up, no downloads, no limits โ just a clear guide whenever you need it. Learn more in the FAQ or About pages.