SHBG optimal range and reference range

Compiled by Alina Radu, founder of Sera, from the published sources below · Last reviewed November 9, 2026

Sera's bands for SHBG, which differ for men and women:

Female: Optimal 40 – 100 nmol/L; sufficient 18.2 – 135.5 nmol/L; out of range below 18.2 or above 135.5 nmol/L.
Male: Optimal 20 – 55 nmol/L; sufficient 13.3 – 89.5 nmol/L; out of range below 13.3 or above 89.5 nmol/L.

Evidence grade: Published reference interval. A band that primarily reflects a published adult laboratory or population reference interval. It is not necessarily applicable to every assay or laboratory.

All units

Unit	Applies to	Optimal	Sufficient	Out of range
nmol/L	Female	40 – 100	18.2 – 135.5	below 18.2 or above 135.5
nmol/L	Male	20 – 55	13.3 – 89.5	below 13.3 or above 89.5

What the evidence says

The bands are a laboratory reference interval (Mayo Clinic Laboratories): 13.3 to 89.5 nmol/L in men and 18.2 to 135.5 in women of reproductive age. Other laboratories print narrower, age-banded limits. No optimal band is published, and the ones shown are functional targets; in cohort data, men with lower SHBG did not fare worse. SHBG is relatively stable across the menstrual cycle but is strongly influenced by thyroid status, insulin and insulin resistance, oestrogen (including oral contraceptives and HRT), body weight and liver function: it is typically low in insulin resistance and PMOS (formerly polycystic ovary syndrome) and high in hyperthyroidism, with oral oestrogen and in anorexia. Interpret it alongside the sex hormones rather than in isolation. These ranges are informative, not diagnostic.

For women: This is an informative female reference range, not diagnostic. SHBG is relatively stable across the menstrual cycle but is strongly influenced by thyroid status, insulin and insulin resistance, estrogen (including oral contraceptives and HRT), and liver function. Interpret it alongside your sex hormones rather than in isolation.

Sources

Sex Hormone-Binding Globulin, Serum (SHBG1) — Mayo Clinic Laboratories, 2026 · Laboratory / reference-interval sourceAdult men aged 18 and over: 13.3 to 89.5 nmol/L. Women aged 18 to 46: 18.2 to 135.5 nmol/L; postmenopausal 16.8 to 125.2. Not established in pregnancy.
Sex Hormone-binding Globulin (test 082016) — Labcorp, 2026 · Laboratory / reference-interval sourceMen 16.5 to 55.9 nmol/L at 20 to 49 years and 19.3 to 76.4 over 49; women 24.6 to 122.0 at 20 to 49 and 17.3 to 125.0 over 49. Narrower than Mayo, and age-banded in men.
Associations of Testosterone and Related Hormones With All-Cause and Cardiovascular Mortality and Incident Cardiovascular Disease in Men: Individual Participant Data Meta-analyses — Yeap BB, Marriott RJ, Dwivedi G, et al. — Annals of Internal Medicine, 2024 · Peer-reviewed publicationIn pooled cohorts of men, the lowest fifth of SHBG (median 20.6 nmol/L) had lower all-cause mortality than the highest fifth (median 68.3). No evidence that a low-normal SHBG in a man is worse. Australian-led, with European and North American cohorts.

What SHBG (Sex Hormone-Binding Globulin) measures

A protein that binds to sex hormones and carries them in the blood.

When SHBG is high, less free hormone is available for the body to use. It is important for understanding overall hormone balance.

Related hormone health markers

See SHBG in the full list of biomarker ranges

This page is a reference for practitioners, not medical advice. Sera's bands are practitioner targets for structured review, not diagnostic thresholds, and Sera does not diagnose or recommend treatment. Read a result alongside the interval printed by the issuing laboratory and the client's history and symptoms. Range set: Sera Production, version 1.0, last reviewed November 9, 2026.