Hydration Calculator

Estimate daily water intake from body weight using a simple general hydration guideline.

A common general guideline is about 30–40 ml per kg. This tool defaults to 35 ml per kg.

Result will appear here.

Privacy: runs locally in your browser. No values are stored or transmitted.

How it works

This calculator estimates daily water intake as: body weight × hydration guideline.

The default guideline used is 35 ml per kg, which is a common general rule-of-thumb, not a medical prescription.

Examples

  • 70 kg × 35 ml/kg → 2,450 ml/day → about 2.45 liters/day
  • 154 lb is converted to kg internally before calculation
  • Useful for simple daily hydration planning

FAQ

  • What does this calculator estimate?

    It estimates daily water intake from body weight using a simple general hydration guideline.

  • What formula does it use?

    This calculator uses a common rule-of-thumb of about 35 ml of water per kilogram of body weight.

  • Is the result exact?

    No. Hydration needs vary with climate, exercise, diet, health status, and medication use.

  • Can I use pounds instead of kilograms?

    Yes. The calculator supports both metric and imperial units.

  • Are my values stored?

    No. All calculations run locally in your browser and are not stored or transmitted.

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