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Free Testosterone Unit Converter
Free Testosterone is the biologically active fraction of testosterone that is not bound to sex hormone-binding globulin (SHBG) or albumin. It represents approximately 1-3% of total testosterone.
Measuring free testosterone is essential for diagnosing hypogonadism in men, especially when SHBG levels are abnormal (e.g., obesity, aging, liver disease). This converter facilitates switching between standard mass units (pg/mL) and SI molar units (pmol/L).
Mass Units
StandardPicograms per milliliter (Common for Free T).
SI Units / Molar
Clinical Context
Reference Ranges (Adult Males):
• Conventional: 47 – 244 pg/mL (approx).
• SI: 160 – 850 pmol/L.
Note on Measurement: Direct analog immunoassays for Free T are often considered less accurate than equilibrium dialysis or calculations based on Total T, SHBG, and Albumin (Vermeulen equation).
Conversion Logic:
Molecular Weight of Testosterone: ~288.42 g/mol.
1 pg/mL ≈ 3.47 pmol/L.
1 pmol/L ≈ 0.288 pg/mL.
Clinical References
How to Use This Converter
Follow these steps to normalize Free Testosterone values.
Enter Values
Input your laboratory results into the corresponding unit field (e.g., pg/mL).
Automatic Conversion
The calculator converts between mass units and the SI molar unit.
Reset
Use the Clear button to reset all fields.
Frequently Asked Questions
Free Testosterone levels are much lower than Total Testosterone. Therefore, picograms (pg) are often used to avoid excessively small decimal numbers.
No, this tool only converts units. To calculate Free T from Total T and SHBG, use a separate “Calculated Free Testosterone” tool.