Skip to main content
Calcimator

Corrected Calcium Calculator

Calculate albumin-corrected serum calcium to account for hypoalbuminemia using the standard correction formula.

Inputs

mg/dL

Normal total Ca: 8.5–10.5 mg/dL; hypocalcemia: <8.5; hypercalcemia: >10.5 mg/dL

g/dL

Normal albumin: 3.5–5.0 g/dL; correction: +0.8 mg/dL Ca per 1 g/dL drop in albumin

Results

Corrected Calcium

9mg/dL

Correction Amount0mg/dL
Measured Calcium9mg/dL
Classification2(1=Low, 2=Normal, 3=High)
How to Use This Calculator
  1. Enter measured serum calcium (mg/dL) and serum albumin (g/dL).
  2. Review Corrected Calcium, Correction Amount, and Classification (hypocalcemia, normal, or hypercalcemia).
  3. Always correct calcium for albumin before interpreting total calcium in hypoalbuminemic patients.

How the result changes with Measured Calcium

Measured CalciumCorrected Calcium
2.92.9mg/dL
7.657.65mg/dL
1313mg/dL
1818mg/dL

What each input means

Measured Calcium
Total serum calcium as reported by the lab in mg/dL. Correction formula: corrected Ca = measured Ca + 0.8 × (4.0 − albumin). Normal total calcium range is 8.5–10.5 mg/dL.
Serum Albumin
Serum albumin level in g/dL. Each 1 g/dL decrease in albumin below 4.0 g/dL lowers total calcium by ~0.8 mg/dL without affecting ionized (active) calcium. Normal range 3.5–5.0 g/dL.

How this is calculated

Worked example, using the default values

  1. Identify Input Parameters
    Measured Calcium = 9, Serum Albumin = 4 = 2 input(s) provided
  2. Calculate Corrected Calcium
    Corrected Calcium
    9 = 9
  3. Calculate Correction Amount
    Correction Amount
    0 = 0
  4. Calculate Measured Calcium
    Measured Calcium
    9 = 9

The questions that sit next to this one — chosen by subject, including calculators filed under a different category.

More in Medical & Clinical.