ZelsawCalc is committed to publishing accurate, evidence-informed health information. This policy explains how we create, review, and maintain our calculators and guides.
Our calculators do not invent their own math. Each one implements a recognized, published formula — such as the CDC BMI categories, the U.S. Navy body-fat method, the Mifflin-St Jeor equation, MET values from the Compendium of Physical Activities, and Naegele's rule for pregnancy dating. We state the method on each calculator so you can verify it.
Health guides and calculators are reviewed by a licensed medical professional, Dr. Ryan Patel, MD, for factual accuracy and to ensure health context is presented responsibly. Nutrition content is additionally informed by our registered dietitian, Sofia Reyes, RD. Medical review checks that our content reflects mainstream medical understanding; it does not create a doctor–patient relationship or constitute personal medical advice.
Where we cite ranges, categories, or guidance, we draw on authoritative public sources including the CDC, NIH, ACOG, the Academy of Nutrition and Dietetics, and peer-reviewed literature. When guidance varies between sources, we say so rather than presenting one number as definitive.
We review content periodically and update it when standards change or when we identify an error. If you spot a mistake, please contact us — we take corrections seriously and will fix confirmed errors promptly.
Health is a “Your Money or Your Life” topic, and we treat it that way. Our tools are for general education and screening only. They cannot diagnose conditions, account for your full medical history, or replace personalized care. Every calculator and article carries a disclaimer urging you to consult a qualified healthcare professional.
ZelsawCalc is supported by advertising served through Google Ad Manager. Advertisers have no input into our formulas, rankings, or health guidance, and we do not present ads as editorial content.
This tool is for general informational and educational purposes only and is not medical advice. It does not diagnose, treat, or replace care from a qualified professional. Always consult a physician or other qualified healthcare provider about your individual health.