Healthy adult women typically have total testosterone levels below 40 ng/dL, with most falling in the 15 to 40 ng/dL range. That’s roughly 10 to 20 times lower than the average man, whose levels range from about 193 to 824 ng/dL. Despite these small amounts, testosterone plays a significant role in women’s health, affecting energy, libido, bone density, and muscle maintenance.
Normal Ranges by Age
Testosterone in women peaks in the late teens and early twenties, then declines gradually from age 20 onward. A woman in her twenties might sit comfortably in the 15 to 40 ng/dL range, while a postmenopausal woman typically falls between 0 and 20 ng/dL. This decline is slow and steady rather than sudden, unlike the more dramatic drop in estrogen that happens around menopause.
Only a tiny fraction of that testosterone circulates freely in the blood. Less than 2% is unbound (“free testosterone”), and in adult women this free portion is typically somewhere between 0.0 and 4.2 pg/mL. The rest is bound to proteins, mainly one called sex hormone-binding globulin, which essentially locks testosterone away so the body can’t use it directly. That distinction between total and free testosterone matters, because two women with the same total level can have very different amounts of usable hormone depending on how much is bound up.
How Women’s Bodies Produce Testosterone
Women make testosterone from three sources in roughly equal shares. The ovaries produce some directly. The adrenal glands, which sit on top of the kidneys, contribute another portion. And the remaining half or so comes from a less obvious route: the body converts precursor hormones (produced by the adrenal glands) into testosterone in tissues like fat, skin, and muscle. This distributed system means that losing one source, such as the ovaries after surgical removal, doesn’t eliminate testosterone entirely but does lower it significantly.
How the Menstrual Cycle Affects Levels
Testosterone does fluctuate across the menstrual cycle, but the changes are subtle. Research tracking salivary testosterone in over 300 women with confirmed ovulation found a slight trend toward a mid-cycle peak around ovulation, followed by a small decrease during the luteal phase (the two weeks before a period). However, the study also found enormous individual variation. Some women showed a clear spike, others showed no pattern at all. So while you might hear that testosterone peaks at ovulation, it’s not a reliable or dramatic shift for most women.
How Birth Control Changes the Picture
Hormonal birth control, particularly oral contraceptives containing estrogen, can substantially lower the amount of testosterone your body can actually use. The pill causes the liver to produce more sex hormone-binding globulin, the protein that locks testosterone up. In one study, women who were current pill users had binding globulin levels four times higher than women who had never used the pill. The practical result: a 40 to 60% reduction in free testosterone. If you’ve noticed changes in libido or energy after starting hormonal contraception, this shift in usable testosterone is one plausible explanation.
The Gap Between Men and Women
A large analysis of healthy adults found that the average range for men starts at about 8.8 nmol/L and goes up to 30.9 nmol/L, while women range from 0.4 to 2.0 nmol/L. The lowest typical value in men is four to five times higher than the highest typical value in women. This creates a clear, bimodal distribution with very little overlap between the sexes. That gap is why testosterone is one of the most sex-differentiated hormones in the human body.
Signs of Too Much Testosterone
When testosterone climbs above what’s normal for a woman, the physical signs tend to be visible. Excess body hair in typically male patterns (chin, chest, abdomen, back), persistent acne, oily skin, thinning hair on the scalp, and irregular or absent periods are the hallmarks. The most common underlying cause is polycystic ovary syndrome (PCOS), which often produces mildly elevated total testosterone. Highly elevated levels can sometimes point to a tumor on the ovary or adrenal gland, though this is rare.
One complicating factor: you can have symptoms of excess testosterone even when your blood levels look normal. Sensitivity to androgens varies from person to person, so some women develop acne or excess hair growth at levels that wouldn’t bother someone else. The reverse is also true. Some women have elevated testosterone on a blood test with no noticeable symptoms.
Signs of Too Little Testosterone
Low testosterone in women is harder to pin down. The most commonly reported symptoms are low libido, persistent fatigue, and a general sense of decreased well-being, but these overlap with many other conditions. One challenge is that current lab tests aren’t especially accurate at the very low end of the testosterone range, making it difficult to confirm whether someone’s levels are genuinely below normal or just at the bottom of the expected spectrum. No testosterone replacement therapy has been formally approved for treating low testosterone in women, though some clinicians prescribe it off-label for sexual dysfunction.
Why the Testing Method Matters
If you’re getting your testosterone checked, the type of lab test used makes a real difference. Standard immunoassay tests, the kind used for most routine bloodwork, were designed to measure the higher concentrations found in men. At the low levels typical in women, these tests become unreliable and can give misleading results. The preferred method for women is a technique called LC-MS/MS (liquid chromatography-tandem mass spectrometry), which is accurate at low concentrations. The Association for Diagnostics and Laboratory Medicine specifically recommends against using standard immunoassay testosterone tests for women and children. If your results seem off or inconsistent, it’s worth asking which method the lab used.