Water per kg Calculator
Calculate daily fluid intake target based on body weight in kilograms
Based on 35 ml per kg of body mass (2450 ml total)
Daily Hydration Schedule
Rehydrates after overnight fluid loss
Sustained cognitive hydration
Compensates for sweat and activity
Gentle hydration without interrupting sleep
Mathematical Formula & Scientific Methodology
Formula: Body Mass Fluid Requirement Rule
Daily Fluid (ml) = Body Weight (kg) × Factor (30 to 40 ml/kg)Clinical rule-of-thumb establishing baseline water turnover requirements for metabolic clearance and thermoregulation.
Model Assumptions
- Normothermic ambient conditions
- Healthy renal function
Variables & Standard Units
| Symbol | Physiological Meaning | Unit |
|---|---|---|
| Body Weight | Measured mass in kilograms | kg |
| Factor | Hydration factor from 30 ml/kg (sedentary) to 40 ml/kg (strenuous exercise) | ml/kg |
Scientific Limitations
- Extreme heat, high humidity, and prolonged endurance exercise require electrolyte replacement in addition to water
Peer-Reviewed Scientific Citations
Obesity: preventing and managing the global epidemic. Report of a WHO consultation (2000)
World Health Organization (2000) — WHO Technical Report Series, 894, 1-253
Key Finding: Standard international adult BMI classifications: Underweight (<18.5), Normal (18.5-24.9), Overweight (25.0-29.9), Obesity Class I (30.0-34.9), Class II (35.0-39.9), Class III (>=40.0).
Frequently Asked Questions
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