What is the Ganzoni formula?

The Ganzoni formula estimates total iron deficit: Total iron (mg) = Weight (kg) × (Target Hb − Actual Hb) g/dL × 2.4 + Iron Stores (mg). The constant 2.4 combines the factors for blood volume (70 mL/kg), hemoglobin iron content (0.34%), and unit conversion.

What iron stores value should I use?

For most adults, 500 mg is used to replenish depleted iron stores. For children under 35 kg, a weight-based value of 15 mg/kg is common. Some protocols use 0 mg if stores are not depleted.

What are normal target hemoglobin values?

Common targets are 13 g/dL for men, 12 g/dL for non-pregnant women, and 11 g/dL for pregnant women. Targets may vary by clinical protocol.

How are the infusion counts calculated?

Each product has a standard dose per infusion (ferric carboxymaltose 500 mg, iron sucrose 200 mg, ferric gluconate 125 mg). The count is the total mg divided by the single-dose size, rounded up to the nearest whole infusion.

Is this calculator a substitute for clinical judgment?

No. This tool is for reference only. Actual dosing decisions should account for patient-specific factors, local protocols, and prescriber judgment.

Iron Dose Total Calculator

Name: Iron Dose Total Calculator
Availability: InStock
Author: Nham Vu

Calculate total IV iron replacement dose using the Ganzoni formula, with a breakdown by common IV iron product sizes.

Patient Parameters

Body Weight (kg)

Actual Hemoglobin (g/dL)

Target Hemoglobin (g/dL)

Common targets: 13 (men), 12 (women), 11 (pregnancy)

Iron Stores Replenishment

Enter patient parameters and press Calculate

Summary

Calculate total IV iron replacement dose using the Ganzoni formula, with a breakdown by common IV iron product sizes.

How it works

Enter the patient body weight in kilograms.
Enter the current (actual) hemoglobin level in g/dL.
Enter the target hemoglobin level in g/dL (commonly 12–13 g/dL for adults).
Select the iron stores replenishment amount (500 mg for adults, or weight-based for children).
The calculator applies the Ganzoni formula and shows total iron dose in mg plus the number of infusions needed for each common IV iron product.

Use cases

Determine total IV iron dose before starting iron replacement therapy.
Plan the number of ferric carboxymaltose 500 mg infusion sessions required.
Calculate iron sucrose 200 mg doses for a full treatment course.
Estimate iron repletion in patients with chronic kidney disease or iron-deficiency anemia.
Guide pre-operative iron optimization in surgical patients.

Frequently Asked Questions

Last updated: 2026-07-23 · Reviewed by Nham Vu