Pediatric Dose Calculator (mg/kg)
What is Pediatric Dose Calculator (mg/kg)
This calculator works out a single weight-based drug dose for a child. Enter the weight and the mg/kg dose and it multiplies them to give the dose in milligrams. An optional maximum single dose caps the result so a heavier child does not exceed the adult ceiling, and an optional liquid concentration converts the milligrams into the volume of syrup or injection to draw up.
How to use
- Enter the child weight in kilograms.
- Enter the dose in mg per kg from your drug reference.
- Optionally set the maximum single dose to cap the result.
- Optionally enter the liquid concentration to get the volume in mL.
When to use it
Working out a paracetamol or amoxicillin dose at the bedside and want the numbers and the volume in one step? Enter a 20 kg child at 15 mg/kg and you get 300 mg; add a 250 mg/5 mL suspension (50 mg/mL) and it shows 6 mL to draw up. Handy at triage, on a drug round, or when double-checking a prescription against the weight.
Frequently asked questions
How does the maximum single dose work?
If you enter a maximum, the calculator caps the result there once the mg/kg dose would exceed it. This mirrors real dosing, where a child near adult weight should not get more than the adult single dose. Leave it blank to see the uncapped mg/kg dose.
How do I turn milligrams into millilitres?
Enter the liquid concentration in mg/mL. A 250 mg per 5 mL suspension is 50 mg/mL, so a 300 mg dose is 6 mL. The calculator divides the dose by the concentration for you.
Is this the total daily dose or a single dose?
It is one administration. If your reference gives a daily dose divided into several doses, enter the per-dose mg/kg, or work out the daily total and divide by the number of doses yourself.
Can I share this calculator with the values pre-filled?
Yes. The URL updates as you type weight, dose and concentration. Copy it from the address bar or use the Copy link button, and anyone who opens it sees the same dose ready to go.
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