How to Test Your Testosterone Levels

Knowing your testosterone level requires more than a single number. A proper hormone panel gives you the full picture of how your HPG axis is functioning — not just whether your testosterone is within a broad reference range. Here is how to test properly and what to do with the results.

When to Test

Testosterone follows a diurnal rhythm, peaking in the early morning and declining through the afternoon. Testing between 7 a.m. and 10 a.m. is essential for accurate results. Tests taken in the afternoon can read 20–30% lower than morning values, potentially misrepresenting your true baseline.

What is the best time to test testosterone?

Between 7 and 10 a.m., when testosterone is at its daily peak. Afternoon tests can read 25–35% lower due to the diurnal rhythm of testosterone secretion. Testing at the same time consistently is essential for accurate comparisons between different measurements.

Avoid testing immediately after intense exercise, illness, major stress, heavy alcohol use, or severe sleep deprivation — all of which temporarily suppress testosterone. If your initial result is low, confirm with a second test on a separate morning before drawing any conclusions.

What to Request

A basic testosterone check (total T only) is insufficient for clinical decision-making. A meaningful baseline panel includes:

What should a complete testosterone panel include?

Total testosterone, free testosterone (or SHBG to calculate it), LH, FSH, and estradiol form the core panel. Adding prolactin, DHEA-S, PSA (if over 40), CBC, and metabolic markers completes the picture. A single total testosterone number is insufficient for treatment decisions.

• Total testosterone — your overall T concentration in blood

• Free testosterone — the biologically active fraction (1–3% of total)

• SHBG (sex hormone binding globulin) — determines how much T is bound vs. free

• LH (luteinizing hormone) — reflects pituitary signaling to the testes

• FSH (follicle-stimulating hormone) — reflects pituitary support for spermatogenesis

• Estradiol (E2) — critical for assessing aromatization and mood/libido balance

• Prolactin — elevated prolactin suppresses T; important to rule out

• CBC (complete blood count) — checks hematocrit as a baseline

• Metabolic panel — liver and kidney function, blood glucose

• Thyroid (TSH at minimum) — thyroid dysfunction affects T significantly

Interpreting LH and FSH

LH and FSH are the signals your pituitary sends to the testes. Low T combined with low or normal LH indicates secondary (central) hypogonadism — the problem is in the signaling chain, not the testes. This is treatable with enclomiphene or HCG. Low T combined with high LH indicates primary hypogonadism — the testes are receiving the signal but not responding. TRT is typically required.

Why test on two separate days before starting treatment?

Testosterone varies day-to-day by 20–30% due to sleep, stress, illness, and circadian factors. A single low reading can be coincidental. Most guidelines require two below-range morning measurements before diagnosing hypogonadism and initiating treatment.

Where to Test

You have several options. Your primary care physician can order this panel. Men's health telehealth platforms often offer comprehensive panels with home blood draws or partner lab visits. Direct-to-consumer lab services (like Ulta Lab Tests or LabCorp OnDemand) let you order panels without a doctor's referral in most US states.

At-home finger-prick tests (like those offered by Lets Get Checked or Everlywell) measure total testosterone only and are less reliable than venipuncture. Use them for convenience but not for clinical decisions.

What do LH and FSH levels tell you that testosterone alone doesn't?

LH and FSH reveal where in the hormonal axis the problem originates. High LH with low T indicates primary hypogonadism (testicular failure). Low or normal LH with low T indicates secondary hypogonadism (pituitary/hypothalamic issue). This distinction determines whether TRT or enclomiphene is more appropriate.

Understanding Your Results

Do not interpret your results against only the lab's reference range. A total T of 315 ng/dL is technically "normal" by many lab standards, but a man experiencing significant low T symptoms at this level has clinically relevant hypogonadism. Interpret results in context of symptoms, free T, and the full panel.

If your total T is below 350 ng/dL on two morning tests with corresponding symptoms, a conversation with a men's health-focused provider about treatment options is warranted.