Estimate how much water you should drink each day based on your body weight and activity.
A common guideline is roughly 30–35 ml of water per kilogram of body weight per day, with more needed when you exercise or live in a hot climate. This calculator starts from your weight, then adds extra for the minutes you exercise and for warmer conditions, giving a practical daily target in litres and cups.
Yes. Around 20% of your daily water typically comes from food, and other fluids like tea, milk and juice contribute too. The figure here is a total daily target; you do not need to reach it from plain water alone.
Very rarely, drinking extremely large amounts in a short time can dilute blood sodium (hyponatremia). For almost everyone, spreading normal intake across the day is safe. If you have a kidney or heart condition, follow your doctor's advice.