Water Intake Calculator
Estimate how much water to drink each day from your weight, exercise and climate, in litres, glasses and ounces.
Runs on your device
Result
Results appear here as you type.
What it does
A common starting guideline is about 35 ml per kg of body weight, plus roughly 350 ml for every 30 minutes of exercise and more in hot weather. Food also supplies about a fifth of daily water.
How to use it
- Enter your weight.
- Add your daily exercise minutes and climate.
- Read your daily target.
Example
The example fills in realistic values and runs the tool. Select Try an example above to see it.
When it helps
- Setting a hydration goal.
- Planning for hot weather or long runs.
- Habit tracking.
Questions
Is this a medical requirement?
No. Needs vary with health, medication and pregnancy. Follow your doctor’s advice if you have kidney or heart conditions.
Does tea or coffee count?
Yes, most drinks contribute to hydration.
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