Hormone panel
Free testosterone
Measured in pg/mL
What it measures
The fraction of testosterone not bound to carrier proteins and therefore available to tissues.
Why it is tracked
Where SHBG is unusually high or low, total testosterone can give a misleading picture. Free testosterone helps resolve that discrepancy and is often the more informative of the two in symptomatic patients with borderline totals.
What a provider considers
- Calculated or measured directly depending on the laboratory method
- Falls as SHBG rises, which happens with age and in thyroid disease
- Interpreted alongside total testosterone and SHBG, not alone
Reference ranges vary between laboratories and a single result rarely means much on its own. Interpretation depends on your symptoms, your other markers and the trend over time — which is what your provider reviews.