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Reading Bloodwork: Testosterone Reference Ranges

February 4, 2025 · 6 min read · Editorial Team

Bloodwork is the only objective way to interpret how a protocol is affecting you. Here’s how to read the key markers.

Total testosterone

Reported in ng/dL or nmol/L (use our unit converter). The eugonadal reference range is roughly 300–1000 ng/dL in most labs, though ranges vary. Our plotter overlays this range for testosterone compounds as a shaded green band.

Free & bioavailable testosterone

Most testosterone is protein-bound (SHBG and albumin). Only free T is biologically active. High SHBG can leave total T normal while free T is low. Use the Vermeulen calculator to estimate free T from total T, SHBG, and albumin.

Estradiol

Aromatization converts testosterone to estradiol. Both high estradiol (gynecomastia, water retention, mood) and crashed estradiol (joint pain, libido loss) are problems. Guided by sensitive LC-MS/MS assay, not the default immunoassay in male ranges.

Lipids and hematocrit

On-cycle monitoring must include lipid panel (AAS lower HDL, raise LDL) and hematocrit (exogenous T raises red blood cells, increasing blood viscosity and cardiovascular risk).