Water Intake Calculator

How much water should you drink a day?

Water helps regulate body temperature, supports digestion, carries nutrients and keeps your joints and skin healthy. How much you need depends mainly on your body weight, how active you are and how hot your surroundings are.

How this calculator works

• Base amount: about 35 ml of water per kilogram of body weight.
• Exercise: about 350 ml extra for every 30 minutes of exercise.
• Climate: an extra 300 ml in warm weather and 500 ml in hot or humid weather, to replace water lost in sweat.

For example, a person who weighs 70 kg, exercises for 30 minutes and lives in a warm climate needs about 2.45 + 0.35 + 0.3 = 3.1 litres of fluid a day.

Tips to drink enough

• Start the day with a glass of water and keep a bottle within reach.
• Drink more before, during and after exercise and in hot weather.
• Pale yellow urine usually means you are well hydrated. Dark yellow suggests you need more.
• Fruit, vegetables, milk, tea and soup all count toward your daily fluid.

Can you drink too much water?

Yes. Drinking very large amounts in a short time can dilute the salt levels in your blood. Sip steadily through the day rather than drinking a lot at once.