Normal Free Testosterone Levels: How to Pay Attention to the Right Values

Here at Anabolic Health, we’ve made it a mission to give you information on how to naturally optimize your testosterone. However, it can be quite hard to get started if you’re not even sure whether you should increase your testosterone in the first place. After all, why would one go through all the trouble if they think they have normal free testosterone levels?


The Different Testosterone Levels You Need to Know

Your body has three different types of testosterone at any given time. These are the following: albumin-bound testosterone, SHBG-bound testosterone, and free testosterone. When your body is tested for total testosterone, the result you get is the sum of these three types being measured.

Free Testosterone

Basically, testosterone that’s not bound in any way is called free testosterone. This is available for use by the body as it can freely pass cell membranes and be used by androgen-responsive cells.

This type of testosterone makes the smallest part in the body’s total testosterone levels, often being just at 2 to 3 percent.

Albumin-Bound Testosterone

This type of testosterone is bound to a protein called albumin, which is created in the liver. Since this testosterone is attached to a protein, your body cannot use right away.

However, due to having relatively weaker binding compared to SHBG-bound testosterone, albumin-bound testosterone spends the least amount of time being inactive or unavailable and more as free testosterone.

For a healthy individual, this type of testosterone is usually at about 50% of the total.

SHBG-Bound Testosterone

SHBG or sex hormone-binding globulin is a protein primarily produced in the liver to inhibit sex hormones like testosterone. This makes any sex hormone bound to it unavailable for use by the body.

Any abnormality in one’s SHBG level would eventually lead to such imbalances in the sex hormone levels as androgen deficiency. Therefore, it’s crucial to have a lifestyle and diet that would promote balance of SHBG levels as too much or too little could result in health problems.

Having too little unbound testosterone, for example, will prove detrimental to your sex drive and might even cause erectile dysfunction. On the other hand, excessive testosterone production (or testosterone supplementation) boosts muscle mass but also increases prostate cancer risk.

Ideally, SHBG-bound or non-bioavailable testosterone should be at 45% of your body’s total testosterone.

expensive test

How Much Is Normal?

As you might have guessed from reading about the different types of testosterone, free testosterone levels are more often the focus of those seeking hormonal balance. However, this does not mean that determining total testosterone levels is less important.

How much total testosterone one has in their system is still a determinant for the health of an individual. Because of this, it’s the free and total testosterone of the body that is often, if not always, measured in different diagnostic tests.

But, this begs the question: “How much of these two should one have?”

Usually, doctors would say that men should have testosterone levels that range between 300 ng/dl and 1050 ng/dl. However, this is too large of a range to be a dependable measure.

Furthermore, studies have shown that older men show symptoms indicating too little (testosterone deficiency) or too much testosterone in their system even when they’re within the normal range of testosterone. This shows that there’s variability as to how much testosterone is ideal depending on the age of an individual.

For this reason, the basis of the optimal level of total and free testosterone is based on averages of testosterone testing done in different age groups.



Below 25
















With the averages of each reference range, you can use this as a rough guideline to compare your total testosterone level to the average within your age range. 

saliva test kit

Measuring Testosterone

Measuring your testosterone can be done either via laboratory blood tests or via saliva and/or urine test kits. Here are some blood-testing methods recommended by the Centers for Disease Control and Prevention (CDC):

  • Liquid Chromatography-Mass Spectrometry (LC/MS)
    LC/MS is praised for its sensitivity and is considered to be the golden standard when testing total testosterone.  However, this method is quite expensive and takes more time to calculate the results.
  • Equilibrium Ultrafiltration
    This method is often used for research purposes, but it’s also a good option for those who want to accurately track their testosterone. Actually, it's seen as the most accurate and dependable way of determining free testosterone levels.

    However, as you’d expect, equilibrium ultrafiltration is more expensive than most other options – and the laboratories capable of conducting it are quite scarce. Therefore, in the absence of this test in your area, an RIA Direct test is deemed adequate.

Aside from blood testing, you can also determine your level of testosterone with test kits that use your urine and/or saliva for samples. These are usually more affordable than a testosterone blood test but are generally less accurate.

Just a Word of Caution

Before you decide to test yourself and determine whether you have clinically low testosterone (otherwise referred to as hypogonadism), understand that your testosterone levels are sensitive to a lot of different factors.

Your current test results could indicate you don’t have enough total and/or free testosterone but a test next week could say you have above-average levels. This is why before you undergo testosterone replacement therapy it’s important that you get yourself tested more than once.

As we’ve said though, blood testing can get a bit pricey and inconvenient. Well, you don’t have to be a candidate for testosterone therapy to have your testosterone test done multiple times. After all, you would want to know whether your efforts in optimizing your testosterone levels are paying off.

This is where urine and saliva test kits become useful – they can easily tell whether you’ve achieved your normal testosterone level. Although less accurate, these are useful in pointing you towards the right direction on how you should proceed in your pursuit for normal free testosterone levels.

Product Image Credits:

Alex Eriksson (Research Analysis)

Alex Eriksson is the founder of Anabolic Health, a men’s health blog dedicated to providing honest and research-backed advice for optimal male hormonal health. Anabolic Health aspires to become a trusted resource where men can come and learn how to fix their hormonal problems naturally, without pharmaceuticals.

Ivan Kokhno (Editor)

Ivan is a medical doctor that has five years experience in researching and writing health-related content, SaaS companies, startups, motivation and self-growth resources. He also speak five languages. Therefore, he is able to research any topic five times better than the average writer.

Leave a Comment