Find out how much water you should drink per day based on your weight, activity level, and climate. Results update instantly.
Water makes up about 60% of your body weight and is essential for almost every bodily function — digestion, circulation, temperature regulation, and carrying nutrients to your cells.
The commonly cited "8 glasses a day" is a rough guideline. Your actual needs depend on your body size, activity level, climate, and diet. Foods like fruits and vegetables also contribute to your daily fluid intake.
Signs of dehydration: dark urine, fatigue, headaches, dry mouth, and difficulty concentrating. The goal is pale yellow urine throughout the day.