Cortisol Blood Test
Cortisol is your primary stress hormone — and a useful marker for sleep, recovery and adrenal function.
What Cortisol measures
Cortisol is produced by the adrenal glands and is your body's primary stress hormone. It follows a strong daily rhythm — highest in the morning to wake you up, lowest at night. Blood cortisol gives a single-point reading; the morning sample is the most clinically useful for screening.
Who should consider checking Cortisol
Have you noticed any of these:
- chronic fatigue or burnout symptoms
- trouble sleeping or waking unrested
- high-stress lifestyle or recent major stressors
- stalled progress in training despite effort
- wanting context for low energy or mood
- tracking the impact of sleep, training or stress-management changes
How the test works
Single blood draw, ideally between 7–9am when cortisol is naturally at its peak. No fasting required. Results back same day.
What "normal" can look like
Reference ranges depend heavily on the time of sample collection because of cortisol's strong daily rhythm. A 'high' result at 8am is normal; the same result at 8pm would be unusual. For dynamic adrenal function tests, your doctor may order multi-point blood or saliva-based tests instead.
Where to get a Cortisol test
Cortisol is included in these panels:
- Men's Hormone Check — A complete picture of male hormonal health — testosterone, the stress and recovery markers, and the brain signals that drive them. A$169
- Core Health Panel — The full check — 42 biomarkers across 8 health areas, in one blood test. Our most comprehensive panel. A$329
Frequently asked questions
Why morning?
Cortisol follows a daily rhythm — highest 6–9am, lowest 11pm–2am. Morning samples are the standard reference point. Same time each test day if you're tracking changes.
Should I fast?
No fasting required.
What does high cortisol mean?
It usually reflects acute stress, illness, or — over the longer term — chronic stress, sleep loss, or in rare cases an underlying adrenal condition. Single readings need context; discuss with your doctor.
Related biomarkers
Guides
- Can You Get a Blood Test in Australia Without a GP Referral? (2026) — Yes — most common blood tests can be self-ordered in Australia. How direct-to-consumer pathology works, what's available, and when you should still see a GP first.
- How Much Does a Testosterone Blood Test Cost in Australia? (2026) — Compare private testosterone blood test prices across Australian providers ($65–$105), what's included in each, and how Medicare item 66695 fits in.