What’s considered normal may also vary slightly depending on the lab that’s counting the cells. Labs vary in terms of the measurements they use. They may also test different samples.  

In healthy adults, a normal CD4(helper T-cells)cell count ranges from 500 to 1,200 cells/mm3 (0.64 to 1.18 × 109/L).

For CD8 (cytotoxic T-cells), a cell count of 150 to 1,000 cells per cubic millimeter is considered normal.