Fresh Frozen Plasma Dose Calculator

Enter Calculation

Patient Weight (kg)

Dose (mL/kg)

Formula

Show calculation steps (2)

1. Estimated Units

   

   Number of FFP units, assuming 250 mL per unit.

2. Typical Dose Range

   

   Usual recommended range using 10 to 15 mL/kg.

Results

Fresh Frozen Plasma Dose

840

mL of FFP

Typical low range (10 mL/kg)	700 mL
Typical high range (15 mL/kg)	1,050 mL
Approx. units (≈250 mL each)	3.36 units

What is the Fresh Frozen Plasma Dose Calculator?

Fresh frozen plasma (FFP) is a blood product used to replace clotting factors in patients with bleeding or coagulopathy, including reversal of warfarin, disseminated intravascular coagulation, and massive transfusion. The standard dosing strategy is weight-based: most guidelines recommend 10-15 mL/kg of body weight. This calculator converts a patient's weight and a chosen dose-per-kilogram into a total plasma volume and an approximate number of units to request.

How to use it

Enter the patient's weight in kilograms and the desired dose in mL/kg (commonly 10, 12, or 15). The tool returns the total FFP volume in millilitres, the typical 10-15 mL/kg range for that patient, and an approximate unit count assuming an average FFP unit volume of about 250 mL. Unit volumes vary by collection method and country, so always confirm the actual volume printed on each bag.

The formula explained

The core equation is simply $$\text{Volume} = \text{Weight} \times \text{Dose-per-kg}$$ For example, a 70 kg patient dosed at 12 mL/kg needs \(70 \times 12 = 840\) mL. Dividing by the average unit volume of 250 mL gives roughly 3.4 units, so you would order 3-4 units. The low and high range values (weight \(\times\) 10 and weight \(\times\) 15) help you bracket a reasonable target.

FFP dose in mL equals patient weight (kg) multiplied by the dose per kg (10-15 mL/kg).

Worked example

A patient weighs 80 kg and the clinician chooses 15 mL/kg. The dose is $$80 \times 15 = 1{,}200 \text{ mL}$$ The 10 mL/kg lower bound is 800 mL and the 15 mL/kg upper bound is also 1,200 mL. At 250 mL per unit, that is about 4.8 units, so order 5 units.

The calculated volume is divided into standard FFP units for transfusion.

FAQ

What dose should I use? Typical adult dosing is 10-15 mL/kg; higher doses may be needed for active bleeding or factor deficiency. Follow your local transfusion protocol.

How many mL is one FFP unit? It varies (roughly 200-300 mL); this tool assumes ~250 mL for the unit estimate. Always verify the volume on the bag.

Is this a substitute for clinical judgment? No. This calculator is an educational estimate. Final dosing must be determined by a qualified clinician based on the patient's condition and lab results.