Corrected Calcium Calculator
Estimate albumin- or protein-corrected calcium with results displayed in mmol/L, mg/L, and mEq/L.
Last updated on: July 6, 2025
Calculate Corrected Calcium
What is corrected calcium?
Total serum calcium is partly bound to proteins (mainly albumin). When albumin is low or high, total calcium may appear falsely low or high.
Corrected calcium uses a formula to adjust measured calcium for albumin (or, less commonly, total protein) when ionized calcium is not available.
Why is this useful?
- Helps interpret total calcium in hypoalbuminemia or hyperalbuminemia.
- Supports screening and follow-up when ionized calcium is not measured.
- Provides quick unit conversions (mmol/L, mg/L, mEq/L) to reduce input errors.
How to interpret the result
Low corrected calcium:
Below the typical reference range (often ~2.20 mmol/L). Clinical correlation is required.
Corrected calcium in a typical reference range:
Often ~2.20–2.60 mmol/L depending on the laboratory. Consider local reference intervals.
High corrected calcium:
Above the typical reference range (often ~2.60 mmol/L). Confirm and evaluate clinically.
Important notes & limitations
Corrected calcium is an estimate. In some situations, correction formulas may be unreliable.
- When accuracy matters (e.g., critical illness, major acid–base disorders), ionized calcium is preferred.
- Different laboratories use different reference ranges; always interpret with the local interval.
- If monoclonal gammopathy is suspected, albumin-based correction is preferred over total protein correction.
This page has been medically reviewed by Dr. Khoulah Attia – PharmD, Immunology Specialist.