Testosterone Analysis Calculator

Evidence-based interpretation of testosterone levels and comprehensive hypogonadism workup following endocrinology guidelines. This tool helps identify appropriate candidates for testosterone therapy and screens for alternative diagnoses.

Proper Testosterone Workup Guidelines

Timing: Two morning (8-10 AM) fasting samples on different days required for diagnosis
Initial labs: Total testosterone, SHBG, LH, FSH, prolactin
Secondary workup: TSH, CBC, metabolic panel, estradiol (if gynecomastia)
Consider: Sleep study (OSA common), iron studies, vitamin D
Diagnosis requires: Low testosterone PLUS symptoms (not symptoms alone)
Red flags: Young age, rapid onset, severe symptoms suggest secondary cause

1. Patient Information

Age (years)

Weight (kg)

BMI (kg/m²)

2. Testosterone Labs

Reference Ranges: Total T: 300-1000 ng/dL | Free T: 5-21 ng/dL | Bioavailable T: 131-682 ng/dL | SHBG: 10-57 nmol/L

Total Testosterone - Sample 1 (ng/dL) *

Morning (8-10 AM), fasting

Total Testosterone - Sample 2 (ng/dL)

Different day, same timing

Free Testosterone (ng/dL)

Direct immunoassay or calculated

Bioavailable Testosterone (ng/dL)

SHBG (nmol/L)

Sex hormone binding globulin

Albumin (g/dL)

For free T calculation

3. Pituitary Hormones

Reference Ranges: LH: 1.7-8.6 mIU/mL | FSH: 1.5-12.4 mIU/mL | Prolactin: 4-15 ng/mL

LH (mIU/mL)

FSH (mIU/mL)

Prolactin (ng/mL)

4. Secondary Workup Labs

TSH (mIU/L)

Hemoglobin (g/dL)

Estradiol (pg/mL)

PSA (ng/mL)

Age >40 before starting TRT

Ferritin (ng/mL)

Vitamin D (ng/mL)

Testosterone Analysis Calculator

Proper Testosterone Workup Guidelines

1. Patient Information

2. Testosterone Labs

3. Pituitary Hormones

4. Secondary Workup Labs

5. Clinical Symptoms & History

Classic Hypogonadism Symptoms:

Alternative Diagnoses to Consider:

Additional History: