What is biological age?

Biological age is a measure of how well your body is functioning compared to your chronological age. While your chronological age is simply how many years you've been alive, your biological age reflects your overall health, lifestyle choices, and how these factors affect your body's aging process. Two people of the same chronological age can have very different biological ages.

How is biological age calculated?

Our assessment evaluates multiple factors that scientific research has linked to biological aging, including physical activity levels, nutrition quality, sleep patterns, stress management, social connections, and lifestyle habits like smoking and alcohol consumption. We use validated algorithms based on peer-reviewed longevity research to estimate your biological age from these inputs.

What factors affect biological age?

Many factors influence biological age, including diet and nutrition, exercise frequency and intensity, sleep quality and duration, stress levels, smoking and alcohol use, social connections, mental health, environmental factors, and genetics. The good news is that many of these factors are within your control and can be modified to improve your biological age.

How accurate is this assessment?

Our assessment provides an estimate based on lifestyle factors and validated research. While it cannot replace clinical biomarkers like blood tests or DNA methylation analysis, it offers valuable insights into how your daily habits may be affecting your aging process. The assessment is most useful as a tool for identifying areas for improvement and tracking progress over time.

Is my data private and secure?

Yes, we take your privacy seriously. All data is encrypted using industry-standard protocols, and we never sell your personal information to third parties. You can delete your data at any time. We comply with GDPR and other privacy regulations to ensure your health information remains confidential.

Can I improve my biological age?

Scientific research shows that biological age is not fixed and can be improved through lifestyle changes. Regular exercise, a healthy diet, quality sleep, stress management, and avoiding harmful habits can all contribute to lowering your biological age. Many users who make consistent lifestyle improvements see positive changes when they retake the assessment.

Terms of Service

Last Updated: July 2026

1. Acceptance of Terms

By accessing the BioAge website or using the Check Biological Age iOS app (together, the "Service"), you agree to be bound by these Terms of Service and our Privacy Policy. If you do not agree, please do not use the Service. You must be at least 18 years old to use the Service.

2. The Service

The Service estimates your biological age from a lifestyle questionnaire based on the validated Frailty Index methodology and, in the iOS app, optionally from metrics you share from Apple Health. Results are statistical estimates for informational and educational purposes and may not reflect your actual physiological state.

3. Not Medical Advice

The Service does not provide medical advice, diagnosis, or treatment. Results, breakdowns, recommendations, and AI-generated interpretations are for general information only and are not a substitute for professional medical evaluation. Always consult a qualified healthcare provider about your health. Never disregard professional advice because of something you read in the Service.

4. Subscriptions and Payment

The core questionnaire and your basic result are free. An optional auto-renewable Premium subscription (weekly or yearly) unlocks the Apple Health calculation, the full category breakdown, personalized recommendations, and AI interpretation in the iOS app. Payment is charged to your Apple ID account at confirmation of purchase. The exact price is always shown in the app before you buy. Where offered, the yearly plan includes a 7-day free trial; you will be charged automatically when the trial ends unless you cancel at least 24 hours before. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period. You can manage and cancel subscriptions anytime in your Apple ID settings. Any unused portion of a free trial is forfeited when you purchase a subscription. Refunds are handled by Apple under their terms.

5. Apple Health Data

If you choose to connect Apple Health, the app reads the metrics you authorize (such as resting heart rate, heart rate variability, VO2 max, steps, sleep, walking speed, and body measurements) with read-only access, and processes them on your device to estimate your biological age. The app never writes to Apple Health. See our Privacy Policy for details.

6. AI Interpretation

The optional AI interpretation feature sends an anonymous summary of your result (no name, no identifiers) to a third-party AI provider for processing when you request it. AI output can be inaccurate or incomplete and is provided for information only. Daily usage limits apply.

7. Acceptable Use and Intellectual Property

You agree not to misuse the Service, attempt to extract its source code or embedded credentials, interfere with its operation, or use it in violation of applicable law. All content, branding, and software in the Service are owned by us or our licensors and are protected by intellectual-property laws.

8. Disclaimer and Limitation of Liability

The Service is provided "as is" and "as available" without warranties of any kind, express or implied. To the maximum extent permitted by law, we are not liable for any indirect, incidental, special, consequential, or exemplary damages arising from your use of, or inability to use, the Service, including decisions you make based on results or interpretations.

9. Changes to These Terms

We may update these Terms from time to time. Material changes will be reflected by the "Last Updated" date on this page. Continued use of the Service after changes take effect constitutes acceptance of the revised Terms.

10. Contact Us

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

support@checkbiologicalage.com