Quick Facts
- Sample: Blood draw from arm
- Fasting: 8–12 hours recommended
- Turn-around: 3-5 days. May take longer based on weather, holiday, or lab delays.
Benefits
- Superior accuracy - Uses equilibrium ultrafiltration method with 97.9% correlation to gold standard
- Comprehensive assessment - Measures both total and free testosterone levels simultaneously
- Fast results - Get your hormone levels within 3-5 days
- No doctor visit required - Order directly and get results confidentially
- Better than calculators - Physical separation provides more accurate free testosterone measurement
- Clinical-grade testing - Same methodology used by major medical centers
Who Is This Test For?
- Men experiencing fatigue, decreased libido, or muscle weakness
- Women with signs of excess testosterone like facial hair or irregular periods
- Individuals with diabetes, obesity, or metabolic conditions affecting hormones
- People monitoring testosterone replacement therapy effectiveness
- Athletes wanting to track natural hormone levels
- Anyone over 45 with unexplained energy or mood changes
How It Works – Just 3 Steps
- Order online - No prescription needed, choose your convenient lab location
- Visit lab - Quick blood draw, fasting preferred, morning collection ideal
- Get results - Secure online portal delivers results in 3-5 days with optional physician consultation
FAQ
What makes this test different from regular testosterone tests? This test physically separates free testosterone using ultrafiltration, providing 97.9% accuracy compared to 66.7% for standard immunoassays.
Do I need to fast before this test? Yes, 8-12 hours fasting is recommended as non-fasting can decrease testosterone levels by up to 28%.
What time should I get tested? Schedule between 7-11 AM when testosterone levels are naturally highest, or within 3 hours of waking for shift workers.
Can women take this test? Absolutely - women benefit from testosterone testing to evaluate conditions like PCOS or unexplained symptoms like hair loss or mood changes.
How often should I retest? For monitoring therapy: every 6-12 months. For initial evaluation: confirm abnormal results with repeat testing on separate occasions.
More Details
What is the purpose of this test?
This test measures both total and free testosterone levels using equilibrium ultrafiltration methodology, providing superior accuracy for hormone assessment (Labcorp 2025). Unlike calculated free testosterone methods, this approach physically separates the free hormone fraction through membrane filtration, offering direct measurement of biologically active testosterone. The test is essential for diagnosing hypogonadism, monitoring testosterone therapy, and evaluating symptoms related to hormone imbalance in both men and women.
Who would benefit from this test?
Men with symptoms of low testosterone including fatigue, decreased libido, erectile dysfunction, or muscle weakness would benefit significantly. Women experiencing signs of excess androgens such as hirsutism, masculinization, or irregular periods should consider testing. Individuals with conditions affecting hormone-binding proteins like obesity, cirrhosis, diabetes, or thyroid disorders particularly benefit from this more accurate free testosterone measurement (Mayo Clinic 2024). The test is also valuable for monitoring testosterone replacement therapy effectiveness.
When should I order this test?
Consider ordering if you're experiencing unexplained fatigue, decreased sex drive, muscle weakness, or mood changes. Men over 45 with concerning symptoms, especially those with diabetes or obesity (BMI >30), should get tested (AUA Guidelines 2024). Women with irregular periods, excessive hair growth, or unexplained weight gain may need evaluation. Athletes or individuals on hormone therapy should test regularly for monitoring purposes.
How do I interpret the results?
Men: 270–1,070 ng/dL
- What it means: Normal range
- Typical action: No action needed
Men: <300 ng/dL
- What it means: Potential deficiency
- Typical action: Consult healthcare provider
Women: 15–70 ng/dL
- What it means: Normal range
- Typical action: No action needed
Women: >70 ng/dL
- What it means: Elevated levels
- Typical action: Evaluate for PCOS or other conditions
Free testosterone typically represents less than 2% of total testosterone but provides better assessment of bioactive hormone levels.
Disclaimer: Reference ranges may vary by laboratory. Listed ranges are general guidelines and may differ from those used by the performing lab. Always consult your healthcare provider for interpretation.
Pre-test preparation
Fast for 8-12 hours before testing for optimal accuracy. Schedule your blood draw between 7-11 AM when testosterone levels peak naturally. Avoid strenuous exercise 24 hours before testing, as this can temporarily affect hormone levels. Inform your healthcare provider about all medications and supplements you're taking, as some can influence testosterone levels (Cleveland Clinic 2025).
How often should I get tested?
- Initial evaluation: Confirm abnormal results with repeat test
- Testosterone therapy monitoring: Every 6–12 months
- General health screening: Every 2–3 years after age 45
- High-risk conditions (e.g., diabetes, obesity): Annually
Why early detection matters
Testosterone deficiency affects 26.6% of adult men in the United States, representing approximately 33.1 million men (AUA Journal 2022). Among men over 45 visiting primary care, 38.7% have hypogonadism, with many cases going undiagnosed. Early detection allows for timely intervention, potentially preventing complications like decreased bone density, cardiovascular issues, and reduced quality of life. The equilibrium ultrafiltration method provides the accuracy needed for confident clinical decision-making.
Related tests you may consider
Sex Hormone-Binding Globulin (SHBG) - Essential companion test that helps interpret free testosterone results by measuring binding proteins, particularly important in obesity and liver disease.
Hormone Check Blood Test Panel measures important hormones like estrogen, progesterone, testosterone, and thyroid levels to help understand how they affect energy, mood, and reproductive health.
Prostate-Specific Antigen (PSA) - Recommended for men over 40 considering testosterone therapy, as baseline PSA levels help guide treatment decisions safely.
