Find out how much water you need to drink per day based on your age, gender, height, weight, activity level and pregnancy status. Use the science-based hydration calculator to estimate your total water intake and fluid intake in different units and adjust for climate and sweating. How much water should you drink each day? It's a simple question with no easy answer. Studies have produced varying recommendations over the years. But your individual water needs depend on many factors, including your health, how active you are and where you live. No single formula fits everyone. How much water you should actually drink isn’t as simple as you’d think. Read about the latest research, tips, what to eat for hydration, and why it’s important. Drinking enough water can help you burn fat and increase your energy levels. This page explains exactly how much water you should drink in a day.