How it's calculated
We use about 33 ml of water per kg of body weight, plus extra for exercise. Hot, humid weather raises your needs further.
Water Intake Calculator
Estimate how much water you should drink a day, based on your weight and exercise.
Rates basis: Estimate
About you
Daily water intake
2.66 L
about 11 glasses a day
Daily water intake: 2.66 L
- Per day
- 2,660 ml
A guide based on ~33 ml per kg, plus more for exercise. Needs rise in heat and humidity.
Example scenarios
70 kg, 30 min exercise
About 33 ml per kg, plus extra for activity.
≈ 2.6 L / day
55 kg, no exercise
Needs rise in Malaysia's heat and humidity.
≈ 1.8 L / day
Understanding the numbers
How the figures above are worked out — the rules, rates and reasoning behind every line.
Estimates only. Results are for planning purposes and may differ from official figures. Confirm against the relevant authority before making financial decisions.
Stay hydrated
Water needs depend mostly on your body weight and how much you sweat. This gives a daily target to aim for.
Frequently asked questions
How much water should I drink a day?
Roughly 33 ml per kg of body weight, plus more when you exercise or it's hot. For a 70 kg person that's around 2.3 litres.
Formula governance
- Formula version
- 2026.1
- Effective date
- 1 Jan 2026
- Government source
- MOH Malaysia · WHO
- Last updated
- 3 Oct 2026