FaridabadBy Dr B.C. Gupta, MD · 2026-08-15
A complete blood count, or CBC, is one of the most common blood tests. It measures the different types of cells in your blood and gives a broad picture of your overall health.
What does the test measure?
A CBC counts and describes three main types of blood cells. Red blood cells carry oxygen around the body. White blood cells help fight infection. Platelets help blood to clot. The test also measures haemoglobin, the oxygen-carrying part of red cells, and haematocrit, the proportion of blood made up of red cells.
How to prepare
A CBC does not usually require fasting. The sample is a blood draw from a vein, and results are typically ready the same day. If your doctor has asked for other tests at the same time that do need fasting, follow the fasting instructions for those.
What the result can mean
Low red cells or low haemoglobin can point to anaemia, which may cause tiredness and weakness. A high white cell count can be a sign of infection or inflammation. A low platelet count can affect clotting. These are general patterns only. A single CBC is not a diagnosis, and your doctor will interpret the numbers together with your symptoms and history.
When is it ordered?
A CBC is ordered for many reasons: as part of a routine health check, to investigate tiredness or unexplained bruising, to look for infection, or to monitor a known condition. It is also a common part of health packages and pre-employment checks.
This article is for general information only and is not medical advice. Always discuss your results and any health concerns with your doctor.
