White blood cells (leukocytes) are your immune system's defenders. The total WBC count, also called TLC (Total Leukocyte Count), shows how many are circulating in your blood.
- Normal range (adults)
- 4–11 ×10⁹/L (4–11 ×10³/µL)
- Sample
- Blood
- Fasting
- Not usually needed
- Also called
- WBC, TLC, White Blood Cell, White Cell Count, Leucocytes, Total Leucocyte Count, Total WBC, Leukocytes
White Blood Cell Count normal range
| Group | ×10⁹/LConventional units: US, South Asia | ×10³/µLSI units: UK, Europe, Australia, international |
|---|---|---|
| Adults | 4–11 | 4–11 |
Your report may use either unit system; labs in the Gulf often print both. Ranges also vary slightly between laboratories, so the range printed on your own report is the one to go by.
Why is the White Blood Cell Count test done?
It is part of the Complete Blood Count and helps doctors spot infection, inflammation, allergy and, less often, blood disorders.
What does a high White Blood Cell Count level mean?
A high WBC count (leukocytosis) usually means your body is fighting something, most often an infection.
Common causes
- Bacterial or viral infections
- Inflammation from injury, surgery or arthritis
- Physical or emotional stress, or heavy exercise
- Smoking
- Steroid medicines
- Allergies and asthma
- Less commonly, leukemia or other bone-marrow disorders
Diet and lifestyle tips
- Rest and stay well hydrated while recovering from an infection
- Eat a balanced diet with fruit, vegetables, yogurt and protein to support immunity
- Stop smoking
- Repeat the test after recovery if your doctor advises
What does a low White Blood Cell Count level mean?
A low WBC count (leukopenia) means fewer infection-fighting cells, so you may catch infections more easily.
Common causes
- Viral infections such as flu or dengue
- Some medicines, including chemotherapy and certain antibiotics or antithyroid drugs
- Autoimmune conditions such as lupus
- Severe vitamin B12 or folate deficiency
- Bone-marrow problems
Diet and lifestyle tips
- Eat enough protein: eggs, fish, chicken, lentils, dairy
- Include foods rich in B12, folate and zinc
- Practise good food hygiene: wash produce, cook meat well, avoid unpasteurised products
- Wash hands often and avoid sick contacts when your count is low
When should you see a doctor?
See a doctor if your count is outside the range together with fever, or if it stays abnormal on repeat testing. A very low count with fever needs urgent care.
Last updated
This page is for general education and is not a diagnosis. Normal ranges differ between laboratories, so always compare your result with the reference range printed on your own report, and discuss abnormal results with your doctor.