Absolute lymphocyte count: Use this tool to estimate

Use this tool to estimate the number of lymphocytes and the CD4 count based on the white blood cell count. Learn how lymphopenia can predict COVID-19 infection and the evidence behind the calculator. Learn what the ALC test measures, how to prepare for it, and what the normal and abnormal ranges are. The ALC test can help diagnose and monitor infections, autoimmune disorders, and cancers that affect the immune system. Learn how lymphocytes help fight infections, what affects their count, and what test results may mean for your health. For adults, the normal range is typically between 1,000 and 4,800 cells per microliter. ALC is more precise than percentages of lymphocytes and is widely used to evaluate immune health. A low ALC, known as lymphopenia, is often a marker of weakened immunity.