Daily Water Hydration Need Formula

Health & Fitness Formula • Published on September 01, 2026 • Last updated September 01, 2026

Mathematical Equation

$$\text{Water (Liters)} = \left(\text{Weight in kg} \times 0.033\right) + \left(\frac{\text{Exercise Minutes}}{30} \times 0.35\right)$$

Variable Definitions

Weight

Body mass in kilograms

Exercise

Daily physical activity duration in minutes

Detailed Explanation

In-Depth Guide

Daily water requirement is calculated based on body weight (approx 35 mL per kg) adjusted for sweat fluid losses incurred during physical exercise workouts.

How to Calculate: Step-by-Step

1. Multiply body weight in kg by 0.033 to calculate base fluid requirement in liters. 2. Add 0.35 liters (350 mL) for every 30 minutes of physical workout exercise.

Worked Calculation Example

70 kg adult exercising 45 minutes daily: - Base = 70 × 0.033 = 2.31 L. - Exercise = (45 / 30) × 0.35 = 0.525 L. - Total Daily Water = 2.83 Liters (approx 11-12 cups).

Common Use Cases

  • Daily health hydration tracking
  • Athletic endurance fluid replenishment
  • Renal wellness

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