Weight-Based Dose calculator
The weight-based dose calculator turns a mg/kg order into a total dose in milligrams for a specific patient weight. You can enter weight in kilograms or pounds and it converts before calculating, which removes the step where most weight-based errors are introduced.
The formula
Total dose (mg) = ordered dose (mg/kg) x weight (kg). When weight is entered in pounds it is converted first, dividing by 2.2046 (1 lb = 0.453592 kg).
A worked example
An order of 15 mg/kg for a patient weighing 154 lb: 154 lb is 69.85 kg, and 15 x 69.85 = 1047.8 mg. Entering 154 as kilograms would have produced 2310 mg — which is exactly why the unit selector exists.
Use an accurate weight
The result is only as good as the weight. A stated or estimated weight, a weight recorded on admission weeks ago, or a bed scale that has not been zeroed will all produce a confident and wrong number. For paediatric dosing especially, use a measured current weight.
What this does not do
This does not know the drug, so it cannot apply a maximum dose, a dose cap, an adjustment for renal or hepatic function, or an age-specific range. It does not check the order or flag an unsafe dose for a particular medication. Every result is a check on your arithmetic, not a clinical decision. Confirm the order, the concentration on the label and your own policy before administering anything.
Frequently asked questions
Can I enter weight in pounds?
Yes. Choose the pound unit and the conversion is applied before the calculation.
Does it check the dose against a maximum for the drug?
No. There is no drug database here. Comparing the result against the safe range for that medication is your step.
Is this suitable for paediatric dosing?
The arithmetic is the same, and paediatric dosing is where an accurate current weight and an independent double check matter most. Follow your paediatric policy.
By The Nursana team · Last updated · Canonical: https://nursana.aoneahsan.com/tools/weight-based-dose
Nursana provides reference tools only and does not give medical, legal or tax advice.