Daily Water Intake Calculator

Hydration is one of the most underestimated pillars of human health, yet most people have no idea how much water they actually need. The old advice to "drink eight glasses a day" is a blunt oversimplification that ignores body weight, activity level, climate and individual physiology. Our daily water intake calculator uses a weight-based formula adjusted for activity level, providing a far more personalised — and physiologically accurate — recommendation than any blanket rule ever could.

Water intake is intimately connected to overall body composition and weight management. Proper hydration boosts metabolic rate, reduces false hunger signals and supports kidney function. If you are on a health journey, we strongly recommend also using our BMI Calculator and Calorie Calculator to build a complete, data-driven picture of your nutritional needs.

⚕️ Please note: The figure provided is a scientifically-based general estimate. Individual hydration needs can vary significantly based on health conditions, medications and climate. If you have kidney, heart or other chronic conditions, please consult your doctor or a qualified healthcare professional for personalised advice.

Quanto água deve ser bebida por dia?

A fórmula geral é 30–35 ml de água por quilograma de peso corporal por dia. Uma pessoa de 70 kg necessita de aproximadamente 2,1–2,5 litros diários em condições normais. A atividade física aumenta esta necessidade em ~500 ml por hora de exercício moderado.

O que acontece quando não bebemos água suficiente?

Uma desidratação leve de apenas 1–2% já prejudica o desempenho cognitivo e a resistência. ⚕️ Consulte o seu médico se tiver doenças renais, cardíacas ou outras condições que afetem a ingestão de líquidos.