Corrected Calcium Calculator Formula
Understand the math behind the corrected calcium calculator. Each variable explained with a worked example.
Formulas Used
Corrected Calcium
corrected_ca = total_calcium + 0.8 * (4.0 - albumin)Adjustment Amount
adjustment = 0.8 * (4.0 - albumin)Variables
| Variable | Description | Default |
|---|---|---|
total_calcium | Total Serum Calcium(mg/dL) | 8.5 |
albumin | Serum Albumin(g/dL) | 3 |
How It Works
Corrected Calcium Formula
Corrected Ca = Total Ca + 0.8 x (4.0 - Albumin)
About 40% of serum calcium is bound to albumin. When albumin is low, total calcium appears low even if ionized (active) calcium is normal.
Normal Ranges
| Test | Normal | |---|---| | Total Calcium | 8.5-10.5 mg/dL | | Albumin | 3.5-5.0 g/dL | | Corrected Ca | 8.5-10.5 mg/dL |
Worked Example
Total calcium 8.5 mg/dL with albumin 3.0 g/dL.
total_calcium = 8.5albumin = 3
- 01Adjustment = 0.8 x (4.0 - 3.0) = 0.8 mg/dL
- 02Corrected Ca = 8.5 + 0.8 = 9.3 mg/dL
- 03Within normal range (8.5-10.5)
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Open Corrected Calcium Calculator