BioT

Bioavailable Testosterone Calculator - Support

About the App

BioT calculates free and bioavailable testosterone from standard laboratory values using the Vermeulen algorithm, a validated method published in the Journal of Clinical Endocrinology & Metabolism.

Features

Calculates both free and bioavailable testosterone
Results shown as absolute values and percentages
Uses the validated Vermeulen algorithm
Simple, clean interface
No account required
Works entirely offline

How to Use

Enter your lab values:

Albumin (g/dL)
Total Testosterone (ng/dL)
SHBG - Sex Hormone Binding Globulin (nmol/L)

Press Calculate to see your free and bioavailable testosterone levels.

Scientific Reference

Vermeulen A, Verdonck L, Kaufman JM. A critical evaluation of simple methods for the estimation of free testosterone in serum. J Clin Endocrinol Metab. 1999 Oct;84(10):3666-72. doi: 10.1210/jcem.84.10.6079. PMID: 10523012.

Frequently Asked Questions

What is bioavailable testosterone?

Bioavailable testosterone is the fraction of testosterone that is available to act on tissues. It includes free testosterone plus testosterone loosely bound to albumin. Testosterone tightly bound to SHBG is not bioavailable.

What is free testosterone?

Free testosterone is the small fraction (typically 1-3%) of total testosterone that is not bound to any protein. It can freely enter cells and bind to androgen receptors.

Why not just measure free testosterone directly?

Direct measurement of free testosterone is technically difficult and many commercial assays are unreliable. Calculated free testosterone using validated algorithms like Vermeulen's method is often more accurate than direct measurement.

Does the app collect any personal data?

No. BioT does not collect, store, or transmit any data. All calculations happen locally on your device. The app does not require an internet connection.

Is this app a substitute for medical advice?

No. This calculator is intended for informational purposes only. Always consult with a qualified healthcare provider for interpretation of laboratory results and medical advice.

Need Help?

If you have questions, feedback, or need assistance, please contact us:

support@maledoc.com