Terms of Service
1. Agreement
By accessing or using thehealthcalc.co (the "Site"), you agree to be bound by these Terms of Service ("Terms"). If you do not agree, do not use the Site.
We may update these Terms from time to time. Continued use of the Site after changes constitutes acceptance of the new Terms. The "Effective" date at the top reflects the most recent revision.
2. Medical disclaimer — please read
The Site is not a medical service. The calculators, guides, percentile lookups, and other content on the Site are provided for general informational and educational purposes only. They are not:
- Medical advice, diagnosis, or treatment.
- A substitute for consultation with a licensed clinician.
- Personalized to your medical history, medications, conditions, or goals.
- A recommendation to start, stop, or change any medication, supplement, diet, or exercise program.
Percentile rankings compare you to a population. They do not predict your individual health, longevity, or risk of any condition. A "low" percentile in a given metric is not, by itself, a diagnosis. A "high" percentile is not, by itself, a clean bill of health.
If you have a medical concern, are considering a change to your health routine, or are interpreting a result that worries you, talk to a qualified clinician. Do not delay seeking professional advice because of something you read or calculated on this Site.
In a medical emergency, call your local emergency number or go to the nearest emergency department.
3. Eligibility
The Site is intended for users 18 years of age or older. The calculators and data are calibrated for adult populations. By using the Site, you represent that you are at least 18. If you are a parent or guardian reviewing the Site on behalf of a minor, the same medical disclaimer applies — the calculators are not designed for pediatric use.
4. Acceptable use
You agree not to:
- Use the Site for any unlawful purpose or in violation of any applicable laws.
- Attempt to access the Site by means other than the interface we provide.
- Scrape, crawl, or systematically copy content from the Site at scale. Search-engine crawlers following robots.txt are welcome; bulk download of pages, calculator code, or NHANES-derived data is not.
- Use the Site or its output to train machine-learning models, large language models, or similar systems without prior written permission.
- Misrepresent the Site's output as medical advice or as a diagnostic result when communicating with others.
- Interfere with the Site's security features or with other users' use of the Site.
5. Intellectual property
All content on the Site — including text, calculator logic, page layout, design, look-up tables, charts, and the underlying data pipeline — is owned by thehealthcalc.co or its licensors, except where noted. The Site's source code for the data-pipeline portion of the project is available under the license specified in our public repository.
Data sources: the underlying NHANES microdata is in the public domain (released by the CDC/NCHS). The percentile lookups, written explanations, and calculator interface are our work. Peer-reviewed study citations remain the property of their original authors and publishers.
You may link to the Site, quote short excerpts with attribution, and share individual calculator pages for non-commercial purposes. You may not republish entire pages, calculator logic, or the full percentile data tables without permission.
6. Calculator accuracy and "as-is" basis
We work hard to make the calculators accurate. The percentile lookups are derived directly from the published NHANES cycles cited on each tool page, and the methodology is described in our Editorial Policy. That said:
- Population data has natural statistical noise. Small differences in percentile should not be over-interpreted.
- Some metrics rely on formulas (e.g., the Boer equation for lean body mass) that are estimates, not direct measurements.
- A self-reported measurement is rarely as accurate as a clinician's measurement.
The Site and its content are provided "as is" and "as available", without warranty of any kind, express or implied, including but not limited to warranties of merchantability, fitness for a particular purpose, accuracy, or non-infringement. We do not warrant that the Site will be uninterrupted, error-free, or that defects will be corrected.
7. Limitation of liability
To the maximum extent permitted by applicable law, thehealthcalc.co and its operators, contributors, and affiliates shall not be liable for any indirect, incidental, special, consequential, or punitive damages, or any loss of profits, revenue, data, or goodwill, arising out of or in connection with your use of (or inability to use) the Site, even if advised of the possibility of such damages.
Nothing in these Terms excludes or limits liability that cannot be excluded or limited under applicable law (including, in the EEA, liability for death or personal injury caused by negligence, or for fraud).
8. Third-party services
The Site uses the following third-party services:
- Hosting — a third-party hosting provider. Your IP address and request metadata are processed by them in accordance with their own policies.
- Google AdSense — for displaying non-personalized advertising. Google's terms and privacy policy apply to advertising-related data. See our Privacy Policy for details.
- Analytics (if used) — a privacy-respecting analytics provider configured to operate without advertising features and with IP anonymization.
We are not responsible for the content, policies, or practices of any third-party service.
9. Indemnification
You agree to indemnify and hold harmless thehealthcalc.co and its operators from any claim, demand, loss, or expense (including reasonable legal fees) arising out of your breach of these Terms or your misuse of the Site.
10. Termination
We may suspend or terminate access to the Site at any time, with or without notice, for conduct that violates these Terms or is otherwise harmful to other users or the Site. The medical disclaimer, limitation of liability, and indemnification provisions survive termination.
11. Governing law
These Terms are governed by the laws of the jurisdiction in which the Site operator is established, without regard to its conflict-of-laws provisions. If you are a consumer in the EEA, UK, or another jurisdiction that provides mandatory consumer protections, those protections apply in addition to this clause.
12. Contact
Questions about these Terms? See our Contact page or email legal@thehealthcalc.co.