Iron Deficit Calculator

Calculate total iron deficit in milligrams using the Ganzoni formula from patient weight, actual Hb, and target Hb.

Patient Parameters

Current measured hemoglobin level

Desired hemoglobin level after treatment

Enter patient data and click Calculate to see the iron deficit.

Summary

Calculate total iron deficit in milligrams using the Ganzoni formula from patient weight, actual Hb, and target Hb.

How it works

  1. Enter the patient body weight in kilograms.
  2. Enter the actual (current) hemoglobin level in g/dL.
  3. Enter the target hemoglobin level in g/dL.
  4. The calculator applies the Ganzoni formula: Iron deficit (mg) = Weight (kg) x (Target Hb - Actual Hb) x 2.4 + Iron stores.
  5. Iron stores are automatically set to 500 mg for patients weighing 35 kg or more, and 15 mg/kg for lighter patients.
  6. Review the calculated total iron dose and per-session split guidance.

Use cases

  • Determine IV iron replacement dose for iron-deficiency anemia.
  • Pre-surgical anemia optimization to reduce transfusion risk.
  • Chronic kidney disease patients requiring iron supplementation.
  • Postpartum iron deficiency management.
  • Inflammatory bowel disease patients with iron malabsorption.
  • Oncology patients with treatment-related anemia.
  • Clinical pharmacists verifying iron infusion orders.
  • Medical students learning the Ganzoni formula.

Frequently Asked Questions

Last updated: 2026-06-09 · Reviewed by Nham Vu