Water Requirement Calculator
Estimate water needs per day based on temperature, exertion and altitude.
How We Calculate This
Base requirement = Body weight × 35ml/kg + Activity hours × 0.6L
Adjusted = Base × Temperature factor × Altitude factor
Temperature: Cool (×0.9), Moderate (×1.0), Warm (×1.3), Hot (×1.6)
Altitude: Low/0-1000m (×1.0), Medium/1000-2500m (×1.15), High/2500m+ (×1.3)
Frequently Asked Questions
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Last updated: February 2026
All calculations are estimates. Always verify conditions and use proper safety equipment outdoors.