Health

Daily Water Intake Calculator

Use a simple weight-based formula to estimate your daily water intake needs.

Calculator

Results

  • Recommended intake
    2.38 L/day
  • Equivalent cups
    10.0 cups/day

General hydration guideline only; adjust for heat, exercise, and medical advice.

Formula

Estimated water intake (L/day) = weight (kg) × 0.033

Use this formula with the live inputs above to test scenarios instantly.

Assumptions

  • Baseline estimate only; needs vary with climate, activity, and medical conditions.

How this formula works

This hydration estimate uses a practical weight-based heuristic to generate a daily baseline target. It is intentionally simple so users can quickly establish a starting point and adjust for real-world factors.

Actual fluid needs vary with climate, sweat loss, activity, medication, and health conditions. Use this output as a planning anchor, then personalize based on your routine and professional guidance if needed.

References & citation

Use these references when documenting assumptions, and copy the block below when citing this calculator.

  • About Adult BMI

    Centers for Disease Control and Prevention (CDC)

    Clinical context for BMI interpretation ranges.

  • Dietary Reference Intakes for Water

    National Academies of Sciences, Engineering, and Medicine

    Commonly cited reference for hydration baseline guidance.

Citation copy block

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