Testosterone Blood Test

Testosterone is a crucial hormone in males and females, affecting sex-drive, energy, mood, fertility, muscle mass and metabolic health.

Our Testosterone Blood Test is a simple blood test you can take at home and send to our lab for analysis to check your testosterone levels.

  • Results and doctor's report in 2 days or less
  • Free, next-working day delivery
  • Optional "free testosterone" test upgrade


Personalise your Testosterone Blood Test

You can choose how you'd like to collect your blood sample. You may also want to add to your test panel depending on your age, sex and any symptoms.

Choose how to collect your blood sample
Add to your test
Dr Alasdair Scott

Dr Alasdair Scott

gut doctor, PhD and our Science Director

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What you need to know about our Testosterone Blood Test

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Dr Alasdair Scott

Dr Alasdair Scott

gut doctor, PhD and our Science Director

Testosterone is a crucial hormone for both men and women. Although women produce less testosterone than men, they still make three to four times as much testosterone as oestrogen.

Low testosterone is common and can cause reduced sex-drive, low energy, infertility, low muscle mass and poor metabolic health. High testosterone can also be a problem in women and is associated with excess hair growth, acne and voice deepening.

What is testosterone?

Testosterone is the main androgenic sex hormone in both men and women. In men, testosterone is produced in the testes in response to stimulation by luteinising hormone from the pituitary gland. In women, most testosterone is produced from the adrenal glands though some also comes from the ovaries.

In both men and women, testosterone plays a role in sex-drive, energy, fertility, muscle mass and metabolic health.

What's the difference between total testosterone and free testosterone?

Total testosterone measures the total concentration of testosterone in the blood. However, most testosterone is actually bound to proteins in the blood (mainly albumin and sex hormone binding globulin) which inactivates it. We can account for this to calculate the amount of "free" testosterone which is actually available for your body. This is a more accurate measure of testosterone status than measuring total testosterone alone.

What causes low testosterone levels?

Testosterone levels fall naturally in both men and women from about 30 years of age. However, about 1-in-4 men over the age of 40 have low testosterone levels for their age. This can be caused by:

  • Obesity
  • Stress
  • Poor sleep
  • Too little exercise (particularly resistance training)
  • Smoking and alcohol
  • Diabetes
  • Steroid use
  • Injury to the testes
  • Pituitary problems, including pituitary tumours

What are the symptoms of low testosterone?

Symptoms of low testosterone include:

  • Erectile dysfunction (in men)
  • Low sex-drive
  • Lack of energy
  • Low mood
  • Infertility
  • Difficulty building muscle
  • Poor metabolic health - high cholesterol and poor sugar-handling

What are the symptoms of high testosterone?

High testosterone levels aren't usually a problem in men but they can cause issues in women. The main causes of elevated testosterone in women are polycystic ovarian syndrome (PCOS) and testosterone replacement therapy. Symptoms of high testosterone levels in women include:

  • Acne
  • Excessive hair growth - e.g. facial hair
  • Deepening of the voice
  • Infertility

What do my testosterone test levels mean?

Testosterone levels are different in men and women.

For men:

Total Testosterone level (nmol/L)Meaning
<8Very low testosterone - likely to benefit from testosterone replacement therapy
8 - 12 (or 8 - 14 if pre-diabetic / diabetic)Borderline low testosterone - may benefit from testosterone replacement therapy
>12 (or >14 if pre-diabetic / diabetic)Normal

For women:

Total Testosterone level (nmol/L)Meaning
0.3 - 1.8Normal

What's tested in your testosterone test?

  • Total Testosterone

    Testosterone is the main androgenic sex hormone in men and women.

Testosterone Blood Test FAQs