Testosterone
The main male sex hormone (also present in smaller amounts in women). Affects muscle, bone, mood, libido, and energy.
Typical reference range
| Range | Unit |
|---|---|
| 8.6–29 (male) | nmol/l |
| 0.3–1.7 (female) | nmol/l |
What Testosterone measures
Testosterone is the body's main androgen, a steroid hormone that is present and important in people of all sexes, though it typically circulates at higher levels in men. It supports libido, muscle and bone strength, mood, red blood cell production, and reproductive function. In everyone, healthy testosterone contributes to energy, body composition, and overall vitality.
Most blood panels report total testosterone, which is often read alongside SHBG (sex hormone-binding globulin) and sometimes free testosterone to reflect how much hormone is actually available to tissues. Levels vary by sex, age, and time of day, and they tend to peak in the morning, so morning sampling matters for a meaningful result. A single reading is best interpreted with a clinician who can consider your history.
What a high Testosterone can mean
What a high testosterone result can suggest depends on your sex and context, and it is not a diagnosis on its own.
- In women and people assigned female: an elevated level can be associated with PCOS (polycystic ovary syndrome) or other endocrine causes, and may accompany symptoms such as acne, unwanted hair growth (hirsutism), or irregular cycles.
- In men and people assigned male: a high reading is commonly linked to testosterone supplementation or other exogenous sources, and only rarely to hormone-producing tumors of the testes or adrenal glands.
- Timing and preparation: because levels shift through the day, sampling that is not done in the morning, recent supplements, or lab handling can produce artifacts.
A high value usually warrants a repeat test and a full clinical picture. Discuss any elevated result with a clinician before drawing conclusions.
What a low Testosterone can mean
What a low testosterone result can suggest also varies, and a single value needs clinical context.
- In men and people assigned male: a low level is commonly associated with hypogonadism, which can arise from the testicles (primary) or from the pituitary and hypothalamus (secondary). It may also relate to aging, obesity, chronic illness, or certain medications.
- Symptoms sometimes reported include low libido, fatigue, low mood, and reduced muscle mass, though these can have many causes and are not specific to testosterone.
- In women and people assigned female: testosterone is measured less often, and interpretation of a low value is more nuanced.
Because testosterone naturally peaks in the morning and fluctuates day to day, a low result often calls for repeat morning testing and evaluation of related hormones. Discuss any low reading with a clinician who can place it in context.
Track your Testosterone over time in Quanome — it reads your lab reports (PDF or photo) on your device, charts each marker against its range, and an AI coach explains what your trends mean alongside your Apple Health and DNA.