What is the normal serum calcium level range?

• A. 7.5-9.0 mg/dL
• B. 8.6-10.2 mg/dL
• C. 9.0-11.0 mg/dL
• D. 10.2-12.0 mg/dL

Answer: (B)

Calcium in the blood is tightly regulated and measured as total serum calcium, which includes calcium bound to proteins and free ionized calcium. The normal total serum calcium range most often used in clinical practice—matching the NCLEX-style reference you’re studying—is about 8.6 to 10.2 mg/dL. This range reflects proper regulation by hormones like parathyroid hormone, calcitonin, and vitamin D, and it helps keep nerve and muscle function, blood clotting, and bone health stable. Values outside this range—lower values indicating hypocalcemia and higher values indicating hypercalcemia—can lead to noticeable symptoms and complications, which is why recognizing the correct normal range is important. The other options fall outside the typical reference interval and are not considered normal for total serum calcium.