Blood Transfusion Volume Calculator

Work out blood transfusion volume instantly with clear inputs, formula shown and shareable results.

About Blood Transfusion Volume Calculator

Uses the paediatric rule that 3 to 5 mL/kg of packed red cells raises haemoglobin by about 1 g/dL, and converts the total into adult unit equivalents.

Formula

Transfusion volume

Volume (mL) = weight (kg) x desired Hb rise (g/dL) x factor (3-5 mL/kg per g/dL)

Worked example

With the default values below, Blood Transfusion Volume Calculator returns Transfusion volume of 160. Change any input above and every figure here is recalculated in your browser.

Inputs used

Body weightaccepts 1–150 kg: 20 kg
Desired haemoglobin riseaccepts 0.5–6 g/dL: 2 g/dL
Volume factoraccepts 3–5 mL/kg per g/dL: 4 mL/kg per g/dL

Results

Transfusion volume: 160 mL
Volume per kilogram: 8.0 mL/kg
Equivalent adult units (280 mL): 0.57

Step by step

1Values used
2Transfusion volume
3Transfusion volume= 160 mL
4Volume per kilogram= 8.0 mL/kg
5Equivalent adult units (280 mL)= 0.57

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.
This is an estimate for general information and not professional medical advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Educational estimate only. Not a substitute for professional clinical judgement, and must not be used to make treatment or dosing decisions.

Frequently Asked Questions

How much does one adult unit raise haemoglobin?

About 1 g/dL in a typical 70 kg adult who is not bleeding.

Should transfusion be single-unit?

Restrictive single-unit transfusion with reassessment is now the standard approach in stable patients.