Is my Free Testosterone normal?
Free blood test checker · Standard + longevity-optimal ranges
What is a normal Free T level?
Free testosterone is the unbound, biologically active fraction — only 2-3% of total testosterone circulates freely. Normal range for men is approximately 5-21 pg/mL; for women, optimal free testosterone sits tightly between 0.5-0.7 ng/dL. Free testosterone is often more clinically relevant than total testosterone when SHBG is abnormal, because SHBG fluctuations can mask true androgen availability. Optimal free testosterone is above 10 pg/mL for men.
| Range | Values |
|---|---|
| Standard Reference | 5–21 pg/mL |
| Optimal | 10–21 pg/mL |
| Low Risk | < 5 pg/mL |
What causes abnormal Free T levels?
Low free testosterone is caused by aging (the most common cause), elevated SHBG (reduces free fraction even with normal total T), obesity (aromatase in visceral fat converts testosterone to estradiol), chronic opioid use, anabolic steroid withdrawal, pituitary dysfunction, and chronic illness. High free testosterone in women may indicate PCOS, adrenal hyperplasia, or androgen-producing tumors.
When should you see a doctor?
See your doctor if free testosterone is below 5 pg/mL, especially with symptoms of hypogonadism: fatigue, low libido, erectile dysfunction, loss of muscle mass, increased body fat, depression, or cognitive decline. Also consult if total testosterone is normal but you have hypogonadal symptoms — free testosterone may reveal the issue.
Free T and longevity
Free testosterone is increasingly recognized as the more clinically relevant androgen measurement. SHBG rises approximately 1-2% per year with age, meaning free testosterone declines faster than total testosterone — by age 70, many men have lost 50-70% of their youthful free testosterone. This decline correlates with sarcopenia, osteoporosis, cognitive decline, and cardiovascular risk. Resistance training, adequate sleep (7-9 hours), body fat reduction, and vitamin D optimization can naturally support free testosterone levels.
Where to get a Free T test
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Related biomarkers
These biomarkers are often tested alongside Free T for a more complete picture.
Frequently asked questions
What is a normal free testosterone level?
Why is free testosterone more important than total?
What causes low free testosterone?
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Sources: Reference ranges based on AHA/ACC, ADA, and AACE clinical guidelines. Biological variation data from Ricos/Westgard database. Longevity-optimal ranges reflect targets used by preventive and functional medicine practitioners.
Last reviewed: April 2026. This tool provides general health information and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult your healthcare provider about your specific results.