What is a normal ionized calcium level?
The short answer
A typical US lab prints a normal ionized calcium range of 4.5–5.3 mg/dL. That range exists to catch disease, not to describe your best.
Nobody we follow has said what your ionized calcium should be. It comes up on the shows, but never with a number.
What ionized calcium measures
Only the free calcium in your blood, the part not attached to proteins.
Labs usually order it when a total calcium result isn't normal. A serious illness or surgery can also upset the balance of free and bound calcium.
Checked against MedlinePlus — Calcium Blood Test.
Common questions
What is a normal ionized calcium level?
Most US labs print 4.5–5.3 mg/dL. Your report grades you against that range. It exists to catch disease, not to describe your best.
What does your ionized calcium number mean?
On a typical lab range, under 4.5 mg/dL is low, 4.5 to 5.3 is normal and over 5.3 is high. Your own report prints its range next to your number, and that is the one your lab uses. Nobody we follow has drawn a line inside that range.
What does the ionized calcium test measure?
Only the free calcium in your blood, the part not attached to proteins. Labs usually order it when a total calcium result isn't normal. A serious illness or surgery can also upset the balance of free and bound calcium.
Why is there no target here?
Because nobody we follow has named a number for ionized calcium. If that changes, it will be here.