Free Androgen Index (FAI) Blood Test

Name: Free Androgen Index (FAI) Blood Test
Brand: Bloody Good
Price: 58.0 AUD
Availability: InStock

$58.00 AUD

Symptoms suggesting high androgens—irregular periods, acne, excess hair growth—or low androgens—low libido, fatigue, poor motivation—and want accurate assessment of available testosterone?

Calculates the ratio of testosterone to sex hormone-binding globulin (SHBG), revealing how much testosterone is actually available to your tissues. Total testosterone can appear normal while FAI shows the true picture.

You will be emailed a referral to take to your local collection centre. If you ever have any questions, we're here to help.

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Private health tests

How It Works

Getting your health measured shouldn't be hard! We're here to help you every step of the way.

Order a test

Order the private test that suits you and your goals. After ordering, you will receive your referral by email.

Collect the sample

Attend one of our 4000+ partner collection centres throughout Australia. Search locations.

Receive your results

View all your lab results in your secure health dashboard. Easy!

Overview

The Free Androgen Index calculates what percentage of your testosterone is actually available to affect your body. SHBG (sex hormone-binding globulin) binds testosterone in your bloodstream, preventing it from entering tissues. FAI reveals whether you have too much, too little, or just enough active testosterone—information that total testosterone alone can't provide.

This distinction matters clinically. A woman with normal total testosterone but low SHBG has high FAI and may experience androgen excess symptoms like acne and unwanted hair growth. Conversely, someone with normal total testosterone but high SHBG has low FAI and may struggle with symptoms of testosterone deficiency despite apparently normal levels.

The test suits Australians investigating PCOS, those with androgen excess or deficiency symptoms, and anyone whose total testosterone doesn't explain their symptoms.

Symptoms

Essential for women with suspected PCOS, androgen excess symptoms (acne, hirsutism), low libido, or anyone needing accurate bioavailable testosterone assessment.

Questions

SHBG binds testosterone, making it unavailable to tissues. FAI accounts for this binding, revealing whether your tissues see normal, high, or low testosterone even when total levels appear acceptable.
Elevated FAI is a key diagnostic criterion for PCOS. It indicates excessive bioavailable testosterone, often causing acne, hirsutism (excess hair growth), menstrual irregularity, and fertility challenges.
Low FAI suggests insufficient bioavailable testosterone, potentially contributing to low libido, fatigue, depression, poor motivation, and reduced muscle mass in both men and women.
SHBG increases with oestrogen, thyroid hormone, and liver disease. It decreases with insulin resistance, obesity, and high testosterone. These factors alter FAI independent of testosterone production.
Treatment targets insulin resistance (metformin, lifestyle changes), reduces testosterone (oral contraceptives, spironolactone), and addresses symptoms individually. Weight loss often improves FAI significantly.
Test during the first week of your cycle (days 1-7) for most consistent results, as testosterone fluctuates slightly throughout the menstrual cycle.

Dr. Vu Tran
Bloody Good’s Chief Medical Officer

How to prepare

No special preparation required. Inform healthcare provider of menstrual cycle timing, hormone medications, and any factors that might affect testosterone or SHBG levels.

After the test

Address elevated FAI through hormone therapy, treatment of underlying conditions like PCOS or insulin resistance, and lifestyle modifications. Work with endocrinologists for complex hormone disorders.

Your test results will be available in your private dashboard. If there are any urgent issues, we'll let you know so you can follow up with your health professional.

Understanding results

Results show Free Androgen Index compared to normal ranges. Elevated FAI may indicate androgen excess, PCOS, or other hormonal imbalances requiring further evaluation.

Testimonials

What Our Customers Say

4.9

Average Rating

5,500+ Customers Tested

250,000+ Individual Biomarkers

Adam O. ACT

Simple health checks in my control

I didn't know that private blood tests were an option. Tried this platform as the packages suited what I wanted for a good price. Easy to follow instructions, and super quick results. Platform provides more information than my gp's ever have on the tests and what the results meant. Would like more clinics to be able to test at (specifically Capital Pathology) but there is a decent network. Will continue to use.

The Performance Check

Wayne S. NSW

Bloody Good

This is a great service, very helpful support, cheaper than going to the doctor for a blood test

Vitamin D (25-OH)

Christopher N. NSW

Quick access to blood tests

BLOODY GOOD is a very efficient route to access blood testing for a visitor outside the Australian health system. It is quick with the necessary referral and documentation, and quick with results. Thank you

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Rebecca Y NSW

Great Service!

Fantastic service to deal with, I love the extra explanations for all the tests.

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Olga B. New South Wales

Convenient

Getting a referral was easy. Laverty pathology accepted it. Bloody Good offers an affordable and convenient way to check essential blood markers.

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Marita S. Queensland

Bloody good test

Very comprehensive tests that have given me a good picture of my overall health.

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Lukas C. NSW

Quick, easy, hassle free

Excellent service, quick, easy, hassle free, can recommend.

Testosterone Free/Total + SHBG

ABDUL S. QLD

Amazingly quick and efficient

Very easy to use. Love that it stores your blood tests.

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Andre D. QLD

5 Stars

Efficient and easy to use

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"I'm a little biased as I work here! However, I love that The Bloody Good Test tracks my health over time. After turning 40, I wanted to make sure I wasn't going to drop dead from something basic I should have known about earlier. Measuring all my core biomarkers each year gives me peace of mind my health is on the right track"

Cameron Smith Head of Ecommerce, Brisbane

Frequently Asked Questions

Do I need to book ahead?

Most collection centres accept walk-ins. Some may require a booking - check details when you click on your chosen location.

How do I know if I need to fast?

If your test needs fasting, we’ll include that in your instructions after you order. Fasting usually means no food for 8–12 hours, but water is fine.

What do I need to bring?

Just your pathology referral form (we email it to you)

Can I bring someone with me?

Of course. Just maybe don’t bring the friend who faints at the sight of blood.

What’s a phlebotomist?

They’re the highly trained professionals who take your blood sample - with a steady hand and a sharp needle. They love blood, but don’t worry… they’re not vampires. Just legends who make blood tests quick, clean, and (almost) painless.

What other samples may I need to provide for my test?

Some of our tests include Urine, Stool, Saliva and more. Each test will have a clear description on what sample you will need to give and instructions on how.