- Fasting and prep
- The Endocrine Society advises a morning draw after fasting. Skip testing while sick or after a bad night of sleep.
- Turnaround
- Usually 1 to 3 days. Some free testosterone methods are sent out and take longer.
- Also called
- free testosterone test, free t test, bioavailable testosterone, testosterone free and total
What it measures
Most testosterone rides on SHBG (sex hormone binding globulin) and albumin. Only a small share floats free. SHBG rises with age, thyroid excess, and liver disease, and falls with obesity and diabetes, so the total can mislead when SHBG is unusual. Labs either measure free testosterone directly or calculate it from total testosterone, SHBG, and albumin. Calculated values are often more reliable than the common direct methods.
Who should consider it
- Men with symptoms of low testosterone
- Men whose total testosterone sits near the low end
- People with obesity, diabetes, or aging-related SHBG changes
- Women with acne, excess hair, or irregular periods, when a clinician suggests it
How to read your result
- Use the ranges printed on your report. Free testosterone ranges vary a lot by method.
- The Endocrine Society asks for symptoms plus consistently low morning levels, confirmed on a repeat test, before diagnosing low testosterone.
- A low free level with a normal total can happen when SHBG is high.
- Women's ranges sit far lower than men's. A mildly high result needs a clinician's review.
Reference ranges differ between labs. Use the range printed on your own report.
What to do next
Repeat a low result on another morning, and ask a clinician about LH, FSH, and prolactin to find the cause. Discuss treatment risks, including effects on fertility, before starting anything.
Where to order Free and total testosterone
These sellers include an independent physician order. You pay online and visit a partner lab. Availability, price, and lab network vary, so confirm at checkout.
Private MD Labs
Online lab seller- Order
- Every order reviewed by a physician. Says you pay $1 to start and the rest after results.
- Results
- Secure online portal with plain-English explanations. Says many results arrive overnight.
HealthLabs
Online lab seller- Order
- Online or by phone. No doctor referral or insurance needed.
- Results
- Secure HealthLabs account. Says 1 to 3 business days.
Walk-In Lab
Online lab seller- Order
- Online, no insurance or doctor order needed. Shows a $6 physician fee per order on popular tests.
- Results
- Online account. Turnaround not stated on its homepage.
Quest Health
Lab-run- Order
- Buy online and book a Quest appointment. An independent provider is involved.
- Results
- Online as soon as ready, with an email alert. Provider discussion included at no extra cost.
Seller details come from each seller's own site and can change. Confirm price, lab location, and state availability at checkout.
Ordering several tests? Plan them together · Filter all sellers
Questions people ask
Is free or total testosterone more accurate?
Both have uses. Total is the starting point, and free helps when SHBG is high or low or the total is borderline.
Why do I need to repeat a low testosterone test?
Levels vary day to day, and illness or poor sleep can drop them. The Endocrine Society recommends confirming a low level before any diagnosis.
Can I order free testosterone without a doctor?
Yes. Many online lab sellers include free and total testosterone, often with SHBG.
Related tests
- Testosterone, totalChecks total testosterone when symptoms suggest it may be low.
- FSH and LHTwo pituitary hormones that drive the ovaries and testes.
- ProlactinChecks a pituitary hormone linked to periods, libido, and milk.
- EstradiolMeasures the main, most active form of estrogen.
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