Reading Bloodwork: Testosterone Reference Ranges

Bloodwork is the only objective way to know what a protocol is doing to your body. Symptoms lie. Reference ranges are imperfect. Numbers on their own mean little without context. The short answer: draw your on-cycle labs at trough (the day before your next injection), order the sensitive estradiol assay, and track the same markers over time so you see trends instead of snapshots. Use the bloodwork tracker to log panels across cycles.

Total testosterone

Total testosterone is reported in ng/dL (US) or nmol/L (international). The eugonadal reference range is roughly 300 to 1000 ng/dL (10.4 to 34.7 nmol/L) in most labs, though ranges vary by lab and by assay. Our unit converter handles the conversion.

Reference ranges are statistical, not optimal. They are usually derived from a population that includes older and unwell men. A 22-year-old at 350 ng/dL is technically “in range” but is probably not feeling great. Individual targets within the band should be set by symptoms, not by the number alone. Our plotter overlays the eugonadal band as a shaded green region for testosterone compounds so you can see where your protocol lands.

On cycle, total T will be well above the reference range for any meaningful AAS dose. That is expected. The question on cycle is not “am I in range” but “where am I relative to where I want to be,” and what the other markers look like.

Free and bioavailable testosterone

Most circulating testosterone is protein-bound, primarily to SHBG (sex hormone binding globulin) and albumin. Only free testosterone is biologically active. A man can have total T in range and still be functionally low if SHBG is very high, because too much of his T is bound and unavailable.

This is why free T often matters more than total T for symptom resolution. Use the Vermeulen calculator to estimate free T from total T, SHBG, and albumin. The Vermeulen equation is the standard direct-calculation method; some labs also offer direct free T measurement via equilibrium dialysis, which is more accurate but more expensive.

SHBG itself responds to AAS use. It typically drops on cycle, which raises free T relative to total T. Estrogen and thyroid status also affect SHBG. If you are symptomatic despite a high total T, check SHBG and free T before raising the dose.

Estradiol

Aromatization converts testosterone to estradiol. On any aromatizing cycle, estradiol rises. Both extremes are problems. High estradiol drives water retention, mood swings, breast tissue sensitivity, and elevated blood pressure. Low estradiol (crashed) drives joint pain, dry skin, flat mood, low libido, and worsened lipids.

This is the most common assay mistake in the AAS world: ordering the default estradiol test. Standard estradiol immunoassays are validated for female ranges and over-read estradiol in men by 20 to 40 percent. Always order the sensitive or LC-MS/MS estradiol assay. It costs slightly more and is worth it. A man with a true E2 of 20 pg/mL may read 35 on the standard assay, and that false reading leads to unnecessary AI dosing. See our AI timing article for the full story.

Hematocrit and hemoglobin

Exogenous testosterone stimulates erythropoiesis (red blood cell production). Hematocrit, the percentage of blood volume that is red blood cells, climbs on cycle. This is one of the most under-monitored risks in TRT and AAS use.

High hematocrit thickens the blood. Above roughly 52 to 54 percent, blood viscosity rises sharply, which increases the risk of clotting, stroke, and heart attack. The clinical intervention for symptomatic high hematocrit is therapeutic phlebotomy (donating blood). Many men on TRT donate regularly to keep hematocrit in a safe range.

Draw hematocrit and hemoglobin on every on-cycle panel. If hematocrit is climbing fast, that is a signal to lower the dose, increase cardiovascular fitness, or arrange a phlebotomy. This marker alone sends more men to the emergency room than any other on-cycle lab.

Lipid panel

AAS affect lipids predictably. They lower HDL (the protective cholesterol) and raise LDL, often dramatically. The effect is dose-dependent and compound-dependent. Testosterone Enanthate at TRT doses has a mild effect. Oral C17-alpha alkylated compounds and high-dose stacks can crush HDL into the single digits within weeks.

A standard lipid panel (total cholesterol, HDL, LDL, triglycerides) is the minimum. On cycle, watch the HDL number and the total-to-HDL ratio. Triglycerides respond to diet and can usually be managed separately. The cardiovascular risk from a wrecked lipid profile is cumulative and does not fully reverse for weeks to months after stopping.

Liver enzymes

For any oral compound, or for any cycle that includes an oral, liver enzymes matter. The minimum panel is AST, ALT, GGT, and bilirubin. AST and ALT rise with hepatic stress. GGT is more specific for cholestatic and alcohol-related liver issues but is a useful adjunct. Bilirubin catches obstruction or severe stress.

Mild AST and ALT elevation (1.5 to 2 times the upper limit) is common on oral cycles and usually reversible after stopping. Persistent elevation, especially with jaundice (yellowing of skin or eyes, dark urine), is a medical emergency. Do not “wait it out” if you see these signs. See our compound interactions article for why stacking orals compounds this risk.

PSA and prostate

PSA (prostate-specific antigen) is a marker for prostate enlargement and prostate cancer risk. Exogenous androgens can grow prostate tissue. A baseline PSA before starting, then annual PSA plus a digital rectal exam after age 40 (earlier with family history), is standard.

A single PSA number matters less than the trend. A slowly rising PSA over years is common with age. A sharp jump warrants urology referral, not self-titration. Prostate health is one of the areas where AAS use intersects with routine medical care, and it should not be skipped.

When to draw labs

Draw on-cycle labs at trough, the day before your next injection. This is when circulating hormone is at its lowest point relative to the peak. If your trough is in range (or where you want it), your peak is higher, which is fine. If you draw at peak, the numbers look great but they tell you nothing about how low you go.

Time your first on-cycle panel at week 4 to 6 (after steady state on a long ester). Draw every 4 to 6 weeks during a cycle. Draw 2 to 3 weeks after any dose change. Post-cycle, draw at 4 to 6 weeks after PCT ends to confirm recovery.

FAQ

What time of day should I draw testosterone labs? Testosterone peaks in the early morning and falls through the day. For baseline (off-cycle) tests, draw between 7 and 10 AM. On cycle, the injection schedule dominates the circadian rhythm, so draw at trough regardless of time of day.

Why is my total testosterone in range but I still feel low? Check SHBG and free testosterone. If SHBG is high, too much of your total T is bound and unavailable. Free T is what your tissues actually use. Also check estradiol, thyroid, iron, and sleep, all of which can cause low-T symptoms with normal total T.

What hematocrit level is dangerous? Above roughly 52 to 54 percent, blood viscosity rises sharply and clotting risk climbs. The exact threshold varies by person and condition. If you are above that range, talk to a clinician about therapeutic phlebotomy rather than ignoring it.

Why do I need the sensitive estradiol test? Standard estradiol immunoassays are calibrated for female ranges and over-read estradiol in men by 20 to 40 percent. The sensitive LC-MS/MS assay is accurate at male levels. The wrong assay leads to unnecessary AI dosing and crashed E2.

How often should I draw bloodwork on cycle? Every 4 to 6 weeks during a cycle, at trough. Add a draw 2 to 3 weeks after any dose change. Post-cycle, draw 4 to 6 weeks after PCT ends to confirm HPG recovery. More frequent is not better; trends matter more than single data points.

Sources

• Bhasin S, et al. Testosterone therapy in men with androgen deficiency syndromes. Endocrine Society Clinical Practice Guideline. 2010. PMID: 20525905.
• Vermeulen A, et al. A critical evaluation of simple methods for the estimation of free testosterone in serum. Journal of Clinical Endocrinology and Metabolism. 1999. PMID: 10523012.
• Coviello AD, et al. Adverse events associated with testosterone supplementation. Journal of the American Medical Association. PMID: 27459173.
• Snyder PJ, et al. The effects of testosterone on hematocrit and lipids in older men. New England Journal of Medicine. 2016. PMID: 26810045.