What is a full blood count blood test?

A full blood count (FBC) is a very common blood test. It’s also sometimes called a complete blood count (CBC) or full blood examination (FBE).

A full blood count can provide information about a range of conditions.

What is being tested in a full blood count?

A full blood count test looks at the number, types and sizes of different cells in your blood, including:

• red blood cells, which carry oxygen around your body
• white blood cells, which fight infection
• platelets, which help blood to clot

Red blood cells

A FBC also measures haemoglobin, the protein that carries oxygen around your body. Haemoglobin (Hb) is found in red blood cells.

Other measurements on red blood cells include:

• haematocrit
• mean cell volume (MCV)
• mean cell haemoglobin (MCH)
• mean cell haemoglobin concentration (MCHC)

These measurements give more information about your red blood cells. They can help your doctor diagnose and understand the cause of conditions such as anaemia.

White blood cells

The number of white blood cells may be reported as part of the FBC. There are many different types of white blood cells. These are:

• neutrophils
• lymphocytes
• monocytes
• eosinophils
• basophils

Knowing the numbers of different types of white blood cells can help with diagnosing conditions and working out the cause of infections.

Why would I need a full blood count?

A full blood count is a very common test. It can be used to screen for, diagnose, and monitor a variety of conditions. It can also be used as part of routine medical testing.

Full blood count testing can be used to look for:

• infections
• anaemia
• causes of tiredness or weakness
• bleeding or clotting problems
• exposure to toxic substances
• response to certain treatments
• vitamin or mineral deficiencies

How to prepare for this test

No preparation is needed for this test.

Understanding your results

It’s important to discuss your test results with your doctor.

There are a wide range of conditions and medicines that can affect your full blood count. Your doctor can interpret your results and explain what they mean for you.

Full Blood Count explanation video

Video provided by Pathology Tests Explained

Resources and support

About full blood count testing

See the Pathology Tests Explained website for more information about full blood count.

You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available 24 hours a day, 7 days a week.

About blood testing

Visit our healthdirect‘s ‘Guide to blood testing’ to learn more about blood tests in general, including information about:

• what happens during a blood test
• the accuracy of your results
• the cost of your blood tests