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Health & fitness

Water needs

Estimate daily water intake from body weight.

Your result

Complete the fields and calculate.

Calculation method and formula

Weight [kg] × 0.035

Understand the inputs

Weight
Unit: kg. Use a measured value or your own assumption.

Assumptions and limitations

The calculation uses a fixed 35 ml/kg. It does not individually separate drinks from food water. Do not use it as a drinking target when medically prescribed fluid limits apply.

The formula uses the specified units. Displayed numbers are rounded; whole packs, item counts and full time periods may also be rounded within the calculation.

Worked example

Illustrative values. Replace them with your own inputs for your calculation.

Weight
75 kg
Example result2.63 l/day

Guide based on 35 ml/kg; climate, exercise and health change needs.

Model revision: October 17, 2026 · How CleverCalc works

FAQ

Frequently asked questions

How does Water needs work?+

Weight [kg] × 0.035. The calculation uses a fixed 35 ml/kg. It does not individually separate drinks from food water. Do not use it as a drinking target when medically prescribed fluid limits apply.

What assumptions should I consider for this result?+

The calculation uses a fixed 35 ml/kg. It does not individually separate drinks from food water. Do not use it as a drinking target when medically prescribed fluid limits apply. The formula uses the specified units. Displayed numbers are rounded; whole packs, item counts and full time periods may also be rounded within the calculation.

How accurate is the result?+

The formula uses the specified units. Displayed numbers are rounded; whole packs, item counts and full time periods may also be rounded within the calculation. Health values are general information, not a diagnosis or personal treatment recommendation.

Is this calculator free?+

Yes. Calculations and PDF export work without an account or registration.

What happens to my inputs?+

Calculations run in your browser. Results are saved locally only when you add them to My results; favourites and history are also local. Shared links contain your values. The currency tool requests the selected currencies from its rate provider without sending your amount.

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