Water Intake Calculator

Q: How is this calculated?

Baseline 30 mL/kg/day, multiplied by activity factor (1.0–1.4) and climate factor (0.9–1.2). It's a practical heuristic.

Weight (kg)

Activity level

Climate

Recommended intake --

In cups (250 mL) --

Guideline only. Individual needs vary; consult a professional if you have medical conditions.

About This Calculator

This calculator estimates daily water intake using a baseline of 30 mL per kilogram of body weight, then adjusts for physical activity level (factor of 1.0 to 1.4) and climate conditions (0.9 for cold/dry up to 1.2 for hot/humid). This heuristic aligns with general hydration guidelines from organizations like the European Food Safety Authority. It is handy for athletes planning fluid intake around training sessions, travelers adjusting to warmer climates, or anyone who simply wants a personalized starting point for daily hydration. Remember that food contributes roughly 20% of total water intake, and individual needs can vary based on health conditions, medications, and altitude.

FAQ

How is this calculated?

Baseline 30 mL/kg/day, x activity factor (1.0-1.4) x climate factor (0.9-1.2). It's a practical heuristic.

Does coffee/tea count?

Mostly yes, but plain water is best. Electrolytes may help with heavy sweating.

Medical considerations

If you have kidney, heart, or endocrine issues, ask your clinician for individualized guidance.

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