Try the calculator
Open calculator →Water Intake Calculator
Use the calculator for your own numbers.
Simple planning method
A common rule of thumb is to begin with a body-weight-based estimate and then adjust for exercise, heat and personal needs.
Hydration needs vary, so a calculator should be treated as a planning aid rather than a medical prescription.
How to use this information
Use the guide to understand the method, then open the calculator to substitute your own values. Small differences in assumptions can produce different answers, so these pages are best used for planning and reference.
General information only: ERICH Calculators provides general-purpose estimates and education. It is not a substitute for professional medical advice, diagnosis or treatment.
Frequently asked questions
Is this an exact medical or nutrition recommendation?
No. It is a general reference estimate only.
Why might two methods give different answers?
Different methods use different assumptions, formulas and reference points.
What calculator should I use next?
Use the linked calculator to enter your own measurements or goals.