Enter the measure total calcium level and albumin level into the calculator to determine the adjusted calcium level.

Adjusted Calcium Formula

The following formula is used to calculate the adjusted calcium level.

AC = C + 0.8 * (4 - P)

Variables:

  • AC is the adjusted calcium level (mg/dL)
  • C is the measured total calcium level (mg/dL)
  • P is the measured albumin level (g/dL)

To calculate the adjusted calcium level, subtract the measured albumin level from 4. Multiply the result by 0.8. Then, add the measured total calcium level to the result.

What is an Adjusted Calcium?

Adjusted calcium, also known as corrected calcium, is a calculation used to assess calcium levels in the blood, taking into account the level of protein, specifically albumin, present. This is because calcium binds to albumin in the blood, and if albumin levels are low or high, it can affect the total calcium level. The adjusted calcium level gives a more accurate reflection of the amount of free, active calcium in the body.

How to Calculate Adjusted Calcium?

The following steps outline how to calculate the Adjusted Calcium level.


  1. First, determine the measured total calcium level (C) in mg/dL.
  2. Next, determine the measured albumin level (P) in g/dL.
  3. Next, use the formula AC = C + 0.8 * (4 – P) to calculate the adjusted calcium level (AC).
  4. Finally, calculate the Adjusted Calcium level.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

measured total calcium level (C) = 8.5 mg/dL

measured albumin level (P) = 3.2 g/dL