Hematocrit
HCT
- Sample
- Blood
- Usual units
- %
Also known as HCT · PCV · Packed Cell Volume · Haematocrit
What this test measures
Hematocrit is the proportion of blood volume occupied by red blood cells. A lab reads it alongside hemoglobin because the two describe the same red blood cell population from different angles — volume share versus protein concentration. It is usually reported as a percentage.
Reading your report
There isn’t one standard range for this test — each lab prints its own. Use the range shown next to your result.
Related guides
- Guide
Why the same blood test has different "normal" ranges at different labs
Reference intervals are built from each lab's own population and equipment, which is why two labs can print different ranges for the same sample.
- Guide
Reference interval, cutoff, and the "optimal" numbers online: three different things
The range beside your result, the target a website quotes, and the threshold that defines a condition are built in different ways and answer different questions.
- Guide
Why the same lab printed a different reference range for you this year
Ranges are not fixed constants. The lab can change method, revise its reference group, or apply a range that depends on your age — none of which is an error.
- Guide
Haemoglobin, haematocrit and the red cell indices: MCV, MCH, MCHC, RDW
A blood count reports the same red cells several ways — a count, a protein, a percentage, and four averages computed from them. What each column is measuring.