How Much Water Should You Drink Each Day?

“Drink eight glasses of water a day” is a popular rule of thumb, but it isn’t based on individual need — actual water requirements vary by body size, activity level, climate, and diet.

What Determines Your Water Needs

Larger bodies generally need more water, as do people who exercise regularly, live in hot or humid climates, or eat a diet lower in water-rich foods like fruits and vegetables. Pregnancy and breastfeeding also increase fluid needs.

A Better Starting Point

Rather than a flat number for everyone, a body-weight-based estimate adjusted for activity and climate gives a more personalised target. Our Water Intake Calculator factors in exactly these variables.

Signs You’re Getting Enough

Urine that’s pale yellow, rarely feeling thirsty, and normal energy levels are good general indicators of adequate hydration for most healthy adults.

Source: National Academies — Dietary Reference Intakes for Water.