Medical Disclaimer

Water Fasting Calc provides general educational information and calculator estimates about extended water fasting and weight change. Nothing on this website is intended to diagnose, treat, cure, or prevent any disease or health condition.

Not medical advice. Always consult a qualified healthcare professional before starting, extending, modifying, or ending a water fast—especially if you are pregnant, breastfeeding, under 18, over 65, take prescription medications, or have any chronic medical condition.

Estimates only. Weight loss projections are mathematical models based on published BMR equations and standard calorie conversions. Individual outcomes vary substantially based on metabolism, body composition, hydration, activity, sleep, stress, and health status. Do not treat calculator output as a guarantee or a clinical prediction.

External links. We link to independent government, medical, and research resources for educational purposes. We do not control third-party content and are not responsible for information on external websites.

Risks of extended fasting

Multi-day water fasting carries documented risks including electrolyte imbalance, dehydration, dizziness, fainting, arrhythmias, hypoglycemia, muscle loss, and refeeding complications. Stop fasting and seek medical care if you experience chest pain, severe weakness, confusion, persistent vomiting, or heart palpitations.

Digital products

Printable planners and guides sold through our Fasting Toolkit are educational planning tools. They do not constitute medical advice and are not a substitute for professional supervision during extended fasting.

By using this website, you agree that Water Fasting Calc and its operators are not liable for any decisions, actions, or health outcomes related to fasting or reliance on calculator estimates.