Hydration calculator guide

How the hydration calculator estimates your daily water target from body weight and activity — plus a simple real-world check.

1 min read

Written & reviewed by Ricardo Tapia·Last updated

The hydration calculator estimates your daily water target from your body weight (~35 ml per kg) plus an allowance for your activity level.

A practical check: apart from the first morning pee, your urine should be light/clear. Drink a glass on waking and one before each meal.

Try it

Get your target in the water-intake calculator, and read the hydration & steps guide for the habits around it.

Sources & references

  • EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific opinion on dietary reference values for water. EFSA Journal. 2010;8(3):1459.
  • Sawka MN, et al. American College of Sports Medicine position stand: exercise and fluid replacement. Med Sci Sports Exerc. 2007;39(2):377-390.

Educational content only. Not medical advice — consult a professional for your situation.