How to Calculate Ideal Daily Water Intake by Weight

Adequate hydration is essential for thermal regulation, digestion, kidney health and cognitive performance. But how much water do you really need to drink every day?

1. The $35\text{ mL por kg}$ Rule of Thumb

The general recommendation from the World Health Organization (WHO) for healthy adults is approximately $35\text{ mL}$ of water for every kilogram of body weight.

$\text{Volume Diário (mL)} = \text{Peso (kg)} \times 35$

Examples:

• Person of $60\text{ kg}$: $60 \times 35 = 2.100\text{ mL}$ ($2,1\text{ Litros/dia}$)
• Person of $80\text{ kg}$: $80 \times 35 = 2.800\text{ mL}$ ($2,8\text{ Litros/dia}$)
• Person from $100\text{ kg}$: $100 \times 35 = 3.500\text{ mL}$ ($3,5\text{ Litros/dia}$)

2. Adjustments for Physical Activity and Weather

If you exercise intensely or live in hot regions, add between $500\text{ mL}$ and $1.000\text{ mL}$ for each hour of training.

3. Make Your Custom Calculation

Access our Water Consumption Calculator to calculate your exact daily goal in cups and liters.