Testosterone Levels in Men by Age, Decade by Decade

Most men look up testosterone levels in men by age with a lab report in hand. You have a number, maybe 412 ng/dL, maybe 14.3 nmol/L, and you want to know where it sits next to other men your age. The figures below come from a 2022 University of Michigan analysis of US survey data, the Massachusetts Male Aging Study and the 2017 harmonized range. Every value is in ng/dL with nmol/L beside it (1 nmol/L equals 28.84 ng/dL).

Testosterone levels in men by age, in ng/dL and nmol/L

No single study covers every decade, so the list runs in two parts. Ages 20 to 44 come from Alex Zhu and colleagues (Journal of Urology, 2022), who split morning testosterone readings from 1,486 men in the US NHANES survey into thirds by age. The first number is where the bottom third ends. The range is the middle third.

• Age 20 to 24: bottom third below 409 ng/dL (14.2 nmol/L); middle third 409 to 558 ng/dL (14.2 to 19.3 nmol/L)
• Age 25 to 29: bottom third below 413 ng/dL (14.3 nmol/L); middle third 413 to 575 ng/dL (14.3 to 19.9 nmol/L)
• Age 30 to 34: bottom third below 359 ng/dL (12.4 nmol/L); middle third 359 to 498 ng/dL (12.4 to 17.3 nmol/L)
• Age 35 to 39: bottom third below 352 ng/dL (12.2 nmol/L); middle third 352 to 478 ng/dL (12.2 to 16.6 nmol/L)
• Age 40 to 44: bottom third below 350 ng/dL (12.1 nmol/L); middle third 350 to 473 ng/dL (12.1 to 16.4 nmol/L)

From 40 up, the Massachusetts Male Aging Study published ranges for healthy, non-smoking men in 2005 (Mohr and colleagues, Clinical Endocrinology). These run from the 2.5th to the 97.5th percentile, so they are wider.

• 40s: 251 to 914 ng/dL (8.7 to 31.7 nmol/L)
• 50s: 216 to 876 ng/dL (7.5 to 30.4 nmol/L)
• 60s: 196 to 859 ng/dL (6.8 to 29.8 nmol/L)
• 70s: 156 to 818 ng/dL (5.4 to 28.4 nmol/L)

The top of the range barely moves between 40 and 79. The floor drops by about 95 ng/dL.

Normal testosterone levels in men, by the main reference ranges

In January 2017, Thomas Travison and colleagues pooled more than 9,000 men from four cohort studies in the US and Europe. Their range for non-obese men aged 19 to 39 is 264 to 916 ng/dL, or 9.2 to 31.8 nmol/L.

The American Urological Association's 2018 guideline uses 300 ng/dL (10.4 nmol/L) as its line for low total testosterone. It asks for two readings on separate days, both taken early in the morning.

Put next to the Michigan figures, a 28-year-old at 320 ng/dL is inside the harmonized range and above the AUA line, yet well inside the bottom third of men his age. Age changes how you should read your own result.

Reading a testosterone chart in nmol/L

Labs in the UK, Australia, New Zealand and much of Europe report in nmol/L. US labs use ng/dL. To convert, divide ng/dL by 28.84, or multiply nmol/L by 28.84. A result of 15 nmol/L is 433 ng/dL. Some labs use ng/mL, which is ng/dL divided by 100, so 4.5 ng/mL equals 450 ng/dL.

How fast testosterone drops after 40

The Massachusetts study followed 1,156 men aged 40 to 70 for seven to ten years, retesting the same men (Feldman and colleagues, 2002). Their total testosterone fell 1.6% a year on average. Free testosterone fell faster, about 2% a year across the group, and bioavailable testosterone fell 2 to 3% a year. Over the same years, SHBG climbed about 1.6% a year.

Run those numbers over a decade. A man at 550 ng/dL at 45 who loses 1.6% a year sits near 468 ng/dL at 55, and his free testosterone has dropped by more than that.

Free testosterone and SHBG, in plain terms

Total testosterone is everything in your blood. Most of it is held tight by sex hormone binding globulin (SHBG), a liver protein. The rest rides loosely on albumin or floats free, and that share is called bioavailable testosterone.

Because SHBG rises with age, two men with the same total can have different free levels. A 62-year-old with a total of 480 ng/dL and a high SHBG can have less free testosterone than a 35-year-old at 400 ng/dL. If your total looks fine and you still feel flat, ask the lab for free testosterone and SHBG on the next draw.

Where pine pollen comes in for men

In 1971, Šaden-Krehula and colleagues isolated testosterone, epitestosterone and androstenedione from Scots pine pollen, the first time testosterone was found in a plant. Our full guide to pine pollen covers its history and how it's made.

Two recent pilot studies gave men a daily pine pollen tincture and measured their blood. In the 2024 study by Neil Wolkodoff, Gregory Haase and colleagues, 10 men aged 47 to 78 took the tincture for 8 weeks. Their average total testosterone went from 362.5 to 448.4 ng/dL (12.6 to 15.5 nmol/L), and their qADAM score, a questionnaire on drive, energy and erections, went from 23.9 to 31.7.

In the 2025 pilot, 11 men aged 25 to 50 took it for 8 weeks. Free testosterone went from 10.48 to 11.72 ng/dL and SHBG fell from 29.1 to 27.4 nmol/L, the two markers that drift the wrong way with age.

Men who take pine pollen daily most often report stronger morning wood and more drive. For more on how men use it, read pine pollen for men.

Mara's Pine Pollen, day to day

Mara's Pine Pollen is wild-harvested, cracked-cell Pinus radiata pollen made into a spagyric tincture. The pollen is extracted, then the minerals left behind are returned to the liquid, so the whole plant ends up in the bottle. Cracking the tough pollen wall before extraction opens the grain up, and a tincture means no powder to mix.

Take 1 to 2 droppers a day. Hold it under your tongue for 20 to 30 seconds and swallow, or stir it into a glass of water. It tastes soft and lightly earthy, with a faint sweetness. One dropper with the morning coffee and one before training is an easy rhythm. A 50 ml bottle lasts 30 to 50 days, so two bottles cover an 8-week stretch with a blood test at each end.

The bottle is dark Miron glass. Dark amber glass is a step in the right direction, but dark Miron glass is the gold standard for keeping light off an extract, and it's what Mara uses.

Pine Pollen considerations

Our recommendation: "Contains alcohol. If you're pregnant, nursing or taking medication, ask your doctor before using it."

Questions men ask about testosterone by age

What is a normal testosterone level for a 40 year old man?

In the Massachusetts Male Aging Study, healthy men in their 40s ranged from 251 to 914 ng/dL (8.7 to 31.7 nmol/L).

What is a normal testosterone level for a 50 year old man?

Healthy men in their 50s in the Massachusetts study ranged from 216 to 876 ng/dL, or 7.5 to 30.4 nmol/L.

Is 15 nmol/L a good testosterone level?

15 nmol/L is 433 ng/dL. For a man of 30 to 44 that lands in the middle third of the NHANES data.

What time of day should testosterone be tested?

Early in the morning, when levels run highest. The AUA asks for two morning readings on separate days before calling a level low.