Water Intake Calculator
Estimate a practical daily hydration target using body weight, activity, and climate.
About the tool
What it does and what to expect
About the tool
What it does and what to expect
A practical hydration starting point
Active adults, office workers, and people spending time in hot climates use hydration estimates to plan water across the day. The calculation starts with body weight and adjusts for exercise and hot or humid conditions.
A worked example
A 70 kg adult exercising for 30 minutes in a mild climate receives a target of about 2.66 litres: roughly 2.31 litres from weight plus 350 ml for activity. Medical conditions, pregnancy, diet, and clinician guidance can change individual needs.
How it works
A simple, local workflow
How it works
A simple, local workflow
- 1Choose units, enter body weight and daily exercise minutes, then select the climate.
- 2The estimate starts at 33 ml per kilogram and adds about 350 ml per 30 minutes of exercise.
- 3A hot-climate adjustment is applied where selected, and the result is shown in litres and approximate cups.
FAQs
Common questions
FAQs
Common questions
How much water should I drink per day?
Needs vary, but weight, physical activity, heat, diet, pregnancy, medication, and health conditions all influence an appropriate amount.
Does coffee or tea count toward hydration?
Most non-alcoholic fluids contribute to total fluid intake, although this tool expresses the target as an equivalent water amount.
Can drinking too much water be harmful?
Yes. Excessive intake can disturb blood sodium levels, so do not force very large amounts and seek medical advice for unusual thirst or fluid restrictions.
Health
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Comments & feedback
Help make this tool better
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