Use this free testosterone calculator to quickly determine your free testosterone levels based on total testosterone and sex hormone-binding globulin (SHBG) values.
Free Testosterone Calculator
Use this calculator to estimate the free testosterone level in the body, which is the testosterone not bound to proteins and thus available for use. To calculate free testosterone, you will need to input your total testosterone, SHBG (Sex Hormone Binding Globulin), and albumin levels.
How to Use
Enter your Total Testosterone value (in nmol/L), SHBG level (in nmol/L), and Albumin level (in g/L) into their respective fields and click on the “Calculate” button. The result will display your estimated free testosterone level in nmol/L.
How It Calculates
The calculator uses an empirical formula that factors in SHBG, albumin, and the constant for albumin’s affinity to testosterone. Free Testosterone is derived from the entered Total Testosterone after adjusting for testosterone bound to SHBG and albumin.
Limitations
The calculations are based on averages and constants which have been found to give a good approximation across many individuals but are not tailored to your specific situation. Factors such as other proteins binding to testosterone or individual variations in protein affinity are not considered. Lab testing is the only way to accurately measure free testosterone levels.