How to use
- Enter your body weight in kilograms.
- Add the number of minutes you exercise on a typical day.
- Use the result as a starting range and adjust for climate, diet and medical advice.
Options explained
- Body weight
- The base range is 30–35 ml of total water per kilogram of body weight each day.
- Exercise
- The estimate adds 500 ml per hour of exercise. Long, hot or very sweaty sessions may require more fluid and electrolytes.
- Food and other drinks
- The result is total water from all sources. Food commonly supplies about one fifth, while milk, tea and other drinks also contribute.
How the estimate is calculated
Daily water = body weight × 30–35 ml, plus about 500 ml for every 60 minutes of exercise.
For example, a 60 kg person who exercises for 30 minutes gets a range of 2,050–2,350 ml a day. This includes water in food and all drinks, so it does not necessarily mean that many millilitres of plain water.
Frequently asked questions
Does coffee count towards water intake?
Yes. Coffee and tea contribute fluid, although large amounts of caffeine may not suit everyone.
Should I always drink the upper end of the range?
No. Thirst, urine colour, weather, activity and diet all matter. More is not always better, and drinking excessive water quickly can be dangerous.
Who should ask a clinician before changing fluid intake?
People with kidney, heart or liver conditions, or anyone prescribed a fluid restriction or diuretic, should follow their clinician's advice.
Privacy
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