Calcium-Phosphate Product (CKD-MBD)

Calcium-phosphate product (serum calcium × phosphate) for CKD-MBD context, against the historical 55 mg²/dL² caution threshold; contemporary KDIGO guidance tracks calcium and phosphate individually.

Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.

Example

Input units
mg/dL (US conventional)
Serum calcium
9.5
Serum phosphate
6.0

Result: Ca × PO₄ 57 mg²/dL² — above the historical 55 caution threshold.

The tool opens with these values already filled in. Replace them with your own.

What the result means

Posture
Historical caution above 55; contemporary KDIGO guidance favors tracking calcium and phosphate individually over the product.

What you enter

  • Input units (mg/dL or mmol/L)
  • Serum calcium
  • Serum phosphate
How this is calculated
Formula
Ca (mg/dL) × PO₄ (mg/dL) in mg²/dL²; SI mmol/L converts first (Ca ×4.008, PO₄ ×3.097).

Kidney Disease: Improving Global Outcomes (KDIGO) CKD-MBD Work Group. KDIGO clinical practice guideline for the diagnosis, evaluation, prevention, and treatment of CKD-MBD. Kidney Int Suppl. 2009;(113):S1-130 (updated 2017). Read the source ↗

A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.

Browse all tools

Built by Clay Good. Source on GitHub.