⚕️ For clinical reference only. Not a substitute for professional judgment.

Corrected Calcium Labs

Adjusts serum calcium for albumin level. Essential when albumin is low — measured calcium underestimates ionised calcium.

Enter values
Awaiting calcium and albumin.

Values

mmol/L
g/L
Formula
SI: Corrected Ca = Measured Ca + 0.02 × (40 − Albumin)
Normal: 2.20–2.60 mmol/L

US: Corrected Ca = Measured Ca + 0.8 × (4.0 − Albumin g/dL)
Normal: 8.8–10.5 mg/dL
When to use
  • Any patient with hypoalbuminaemia — liver disease, malnutrition, critical illness
  • Low albumin causes measured Ca to be falsely low
  • If corrected calcium is still low → true hypocalcaemia (check PTH, Mg, vit D)
  • Consider ionised calcium (ABG) when in doubt — most accurate