Testosterone, Free
The biologically active fraction of testosterone, most useful when SHBG is skewing the total.
Consider this test if:
- Low libido, fatigue, low mood, or loss of muscle mass with a borderline total testosterone
- Obesity, diabetes, thyroid or liver disease, or another condition that alters SHBG
- Hirsutism, acne, irregular cycles, or suspected PCOS in women
- Confirming a hypogonadism workup when total testosterone alone is ambiguous
- Monitoring androgen status on testosterone therapy or anti-androgen treatment
- HSA/FSA eligible
- Typical results in 2-4 days · Reviewed by a real clinician
- Drawn at a CLIA/CAP-accredited lab near you ·
Pre-test considerations
Draw in the morning, ideally before 10 am, when testosterone peaks. Fasting is generally recommended, since recent meals can affect the result. Note any testosterone, steroid, or anticonvulsant use, as these shift both testosterone and SHBG. A low or borderline result is usually confirmed with a repeat fasting morning draw before any conclusion.
Video consult with your Care Team
A 1:1 call to discuss your health.
What members say on Trustpilot
What this test is for
Free testosterone is the small portion (roughly 2 to 4 percent) of testosterone that is unbound and biologically active, while most testosterone circulates bound to SHBG and albumin. It is typically derived from measured total testosterone, SHBG, and albumin, and it becomes more informative than total testosterone alone when SHBG is altered by obesity, diabetes, thyroid disease, liver disease, aging, or certain medications. In men, low free testosterone is investigated alongside symptoms of hypogonadism such as low libido, fatigue, reduced muscle mass, erectile difficulty, and low mood; in women, high free testosterone is a sensitive marker for hyperandrogenism, hirsutism, acne, and PCOS.
This is the free fraction; the separate Total Testosterone test is the standard morning screening number, and Bioavailable Testosterone adds the loosely albumin-bound portion. Free testosterone is the form to add when total sits near the lower limit or when a condition is shifting SHBG.
What to expect
- 1 Book instantly
Click, book, done. Choose a convenient lab location near you. Transparent, up-front pricing.
- 2 Quick lab visit
Testing to fit your busy schedule, usually 15 minutes or less. Walk-in and appointments available.
- 3 Typical results in 2-4 days
Your results post straight to your dashboard as soon as the lab completes them.
- 4 Expert guidance
Included with Mito membership. A clinician reviews your results and your personalized action plan follows, with clear next steps.
Everything your health needs,
in one membership
-
Every test at our cost
Members pay our cost on every test, with lab fees passed straight through. The full receipt is itemized, never padded.
-
Continuous tracking, all in one place
Upload past labs and watch your trends over time. Every marker and visit lives in one longitudinal record, so all your care stays together.
-
Year-round clinician support
Text anytime and get clinician-reviewed answers. When you want to go deeper, 1:1 consultations are available at affordable rates.
All for $9/month
Order any test or consult without joining. For $9/month, members unlock member prices, trend tracking, and year-round clinician guidance.
Mito Membership
$9 /mo
cancel anytime
Without membership
$0
pay as you go
At-cost pricing on labs, scans, and more
Priority turnaround on your results
On-demand clinician consults when you need guidance
Personalized action plans across supplements, exercise, nutrition, and sleep
AI health coaching to help you act on your results
Year-round medical support, with in-chat clinician escalation
All your health records in one personal vault, with trends and biological age tracking
Early access to new diagnostics and product releases
More tests to consider
Loading essentials…
Frequently asked questions
View all FAQsHow does pricing work?
Every test shows the member price next to the standard non-member price, so you can see what membership saves you. The member price is our cost — covering the lab and what it takes to run the service — never a profit on the test itself; Mito makes its money on the $9 membership, not on marking up your tests. Membership is $9/mo, and you still pay the lab’s order fee. Prices are itemized before you pay, with no hidden fees.
Where do I get tested?
Choose a partner lab (Quest, Labcorp, or BioReference) at checkout. If your cart spans multiple tests, we consolidate the whole order onto a single lab so you only make one visit.
Is this eligible for HSA/FSA?
Yes. This test is HSA/FSA eligible, and you can pay with your HSA/FSA card at checkout.
When will I get my results?
Your results post to your dashboard once your lab completes them, then a clinician reviews them and your full analysis and personalized action plan (with clear next steps) follow. Turnaround varies by test: specialty assays and at-home kits take longer, and each test shows its expected turnaround before you buy.
Do I need a doctor’s order?
No. Mito provides the lab order for you, so you can book and get tested without a separate doctor visit.
Recently viewed
Loading essentials…