What Testosterone measures
Testosterone is a hormone made mainly by the testes in men and in smaller amounts by the ovaries and adrenal glands in women. Most tests measure total testosterone.
Much of it is bound to a carrier protein called sex hormone-binding globulin (SHBG), so many panels also report SHBG and a calculated free testosterone, which estimates the active portion.
Why it matters for longevity
Testosterone influences muscle mass, bone density, red blood cell production, mood, energy and libido. In men, levels tend to decline gradually with age, and lower levels often go together with poor sleep, excess weight and metabolic problems.
In women, testosterone is part of a wider hormone picture and is usually tested with other hormones. A single number rarely explains symptoms on its own, which is why results are best reviewed with a doctor alongside how you feel.
How it's tested
- Sample
- Finger-prick or venous
- Fasting
- Some providers recommend fasting, as eating can lower levels slightly
- Units
- nmol/L in the UK and Europe, ng/dL in the US
Before you test
- Testosterone is highest in the morning – most labs ask for a sample before 10 or 11 am.
- Avoid testing after a poor night's sleep, during illness or right after intense training.
What can affect your result
- Time of day
- Sleep, illness and intense training
- Body weight and alcohol
- Medicines and supplements, including hormonal treatments
Talking to your doctor about your result
Your report will show your result next to the lab's reference range. Ranges differ between labs and units, and a result inside or outside the range isn't a diagnosis on its own. Share the full report with your doctor – especially if a result is flagged, you have symptoms, or there's a family history that concerns you. Don't start, stop or change any medicine or supplement based on a home test without medical advice.
What a Testosterone test costs
In our European price check (12 October 2026), the cheapest Male hormones test or small panel we found was €22 (Werlabs, Sweden); the cheapest option in the most expensive country was €94 (United Kingdom). Lab prices often exclude a small blood-draw or visit fee. It can be better value as part of a panel if you want several of the core markers. See every price by country in our European blood test price guide.
Testosterone: common questions
Why does the time of day matter?
Testosterone follows a daily rhythm and is highest in the morning. A sample taken in the afternoon can read noticeably lower, so test in the morning and at a similar time if you re-test.
What is SHBG?
Sex hormone-binding globulin is a protein that carries testosterone in the blood. Only the unbound portion is readily available to tissues, so SHBG helps put total testosterone in context.
Is a testosterone test useful for women?
It can be, as part of a wider hormone panel. Women's levels are much lower than men's, and interpretation depends on age, cycle and other hormones – so review results with a doctor.
Related markers
Sources
[PLACEHOLDER: 2–4 primary references (guidelines, consensus statements) confirmed by the medical reviewer]