Terms of Service

Acceptance of Terms

By accessing and using this website (leanbodymasscalculator.org), you acknowledge that you have read, understood, and agree to be bound by these Terms of Service. If you do not agree with any part of these terms, please do not use this website.

These terms apply to all visitors, users, and others who access or use the website and its calculators.

Description of Service

Lean Body Mass Calculator provides free online calculator tools that estimate body composition metrics, including:

• Lean body mass calculations
• Body fat percentage estimates using the Navy method
• Body composition breakdowns
• Natural muscle potential estimates
• Protein intake recommendations

The service is provided free of charge, requires no account or registration, and is accessible via standard web browsers. All calculations are performed locally in your browser using JavaScript.

Disclaimer of Warranties

The calculators and information on this website are provided for educational and informational purposes only. They are not intended to be, and should not be construed as:

• Medical advice or diagnosis
• Nutritional or dietary counseling
• Professional fitness or training guidance
• A substitute for consultation with qualified healthcare providers

The calculations provided are estimates based on mathematical formulas derived from population studies. Individual results may vary significantly based on factors these formulas cannot account for, including genetics, health conditions, body composition variations, and measurement accuracy.

Always consult with qualified healthcare providers, registered dietitians, or ACSM-certified fitness professionals before making decisions about your health, diet, or exercise program based on any calculations or information from this website.

Limitation of Liability

To the fullest extent permitted by applicable law, the operators of this website shall not be liable for any direct, indirect, incidental, special, consequential, or punitive damages arising out of or relating to:

• Your use of or inability to use the website or calculators
• Any decisions, actions, or outcomes based on calculator results
• Any errors, inaccuracies, or omissions in the calculations or content
• Any health, fitness, or dietary decisions influenced by information on this site
• Any interruption or cessation of the service

You use this website and its calculators entirely at your own risk. The website is provided "as is" and "as available" without warranties of any kind, either express or implied.

Accuracy

We strive for accuracy in our calculations by implementing established, peer-reviewed formulas used in sports science and nutrition research. These include:

• The Boer formula for lean body mass estimation
• The U.S. Navy method for body fat calculation
• The Martin Berkhan formula for muscle potential
• Evidence-based protein intake ranges

However, we do not guarantee the accuracy of any results. These formulas have known limitations and standard errors. For precise body composition measurements, laboratory methods such as DEXA scanning, hydrostatic weighing, or air displacement plethysmography are recommended.

The formulas, methodologies, and reference data used are documented on our About page and in our educational guides.

Permitted Use

You may:

• Use the calculators for personal, non-commercial purposes
• Link to any page on this website from your own website, blog, or social media
• Share links to the calculators with others
• Reference the formulas and methodologies with appropriate attribution

You may not:

• Scrape, crawl, or use automated tools to extract content or data from this website
• Embed the calculators in an iframe or integrate them into another website without prior written permission
• Copy, reproduce, or republish substantial portions of the website content
• Use the website in any way that could damage, disable, or impair the service
• Attempt to gain unauthorized access to any part of the website or its systems
• Use the website for any unlawful purpose

If you wish to embed the calculator or use our content commercially, please contact us to discuss licensing or partnership arrangements.

Intellectual Property

The website design, layout, graphics, text content, and code are protected by intellectual property laws. You may not copy, modify, distribute, or create derivative works without permission.

Exception: The mathematical formulas themselves (such as the Boer formula, Navy body fat formula, etc.) are in the public domain and are not proprietary to this website. Our implementation, presentation, and explanatory content are protected, but the underlying mathematics is freely available for anyone to use.

External Links

This website may contain links to external websites or resources. These links are provided for convenience and informational purposes only. We do not endorse, control, or take responsibility for the content, privacy policies, or practices of any third-party websites.

Accessing external links is at your own risk. We encourage you to review the terms and privacy policies of any third-party sites you visit.

Modifications to Terms

We reserve the right to modify these Terms of Service at any time. When we make changes, we will update the "Last Updated" date at the bottom of this page.

Your continued use of the website after any changes constitutes your acceptance of the new terms. If you do not agree with modified terms, you should discontinue use of the website.

We encourage you to review these terms periodically for any changes.

Termination

We reserve the right to restrict or terminate access to the website for any user who violates these Terms of Service or uses the website in a manner that we determine, in our sole discretion, to be harmful, fraudulent, or otherwise inappropriate.

We may also modify, suspend, or discontinue the website or any part of it at any time without notice.

Severability

If any provision of these Terms of Service is found to be unenforceable or invalid by a court of competent jurisdiction, that provision shall be limited or eliminated to the minimum extent necessary so that the remaining provisions shall otherwise remain in full force and effect.

Entire Agreement

These Terms of Service, together with our Privacy Policy, constitute the entire agreement between you and the operators of this website regarding your use of the website and calculators, superseding any prior agreements.

Contact

If you have questions about these Terms of Service, please contact us:

Email: info@leanbodymasscalculator.org

Last Updated: January 2026