Haematocrit: normal range and what it means
The proportion of blood made up of red cells.
Normal range
This marker’s healthy range depends on sex and age.
| Normal range | Men | Women |
|---|---|---|
| Low | < 38.3 % | < 35.5 % |
| Normal | 38.3 – 48.6 % | 35.5 – 44.9 % |
| High | ≥ 48.6 % | ≥ 44.9 % |
What it measures
The share of your blood volume made up of red cells. It tracks haemoglobin closely and rises with dehydration, altitude and smoking.
What moves it
Hydration first — being dry concentrates the blood and raises it. Also altitude, smoking, iron status and testosterone.
How to bring it into range
Drink normally before a draw, since dehydration alone can push it up. A genuinely high result is worth investigating rather than ignoring.
How fast it responds
Days for hydration, weeks to months for anything real.
Also reported as: hct · pcv · packed cell volume
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Common questions
- What is a normal Haematocrit level?
- Normal: 38.3 – 48.6 %. This marker’s healthy range depends on sex and age.
- What does a high Haematocrit mean?
- A value above the reference band means Haematocrit is outside the range typical for a healthy adult. A single reading is rarely conclusive on its own — what matters is the trend across draws and the other markers around it, which is why HealthOS reads the whole panel together rather than one number at a time.
- How do I improve my Haematocrit?
- Drink normally before a draw, since dehydration alone can push it up. A genuinely high result is worth investigating rather than ignoring.
Related markers
More in Complete Blood Count
Reference ranges are general-population guidance compiled from common clinical laboratories, not a diagnosis. Lab-to-lab ranges differ. Always read your results with your doctor.