Medication Dose by Weight Calculator
Weight-based dosing with volume per dose.
Enter your values
ⓘ Live results
Results
- Dose per administration
- 270 mg
- Volume per dose
- 11.3 ml
- Total daily dose
- 1080 mg
- Daily volume
- 45 ml
Working
- 118 kg x 15 mg/kg = 270 mg
Quick answer
Weight-based dose is mg per kg times body weight; volume is that dose divided by the concentration.
volume = (dose mg/kg x weight) / concentration
How to use the Medication Dose by Weight Calculator
- 1Enter the patient weight in kilograms.
- 2Enter the prescribed mg/kg dose and the product concentration.
- 3Always confirm against the prescription and product label before administering.
Worked example
Using the values the calculator loads with:
Inputs
- Body weight18 kg
- Dose15 mg/kg
- Concentration120 mg per 5 ml
- Doses per day4
Results
- Dose per administration270 mg
- Volume per dose11.3 ml
- Total daily dose1080 mg
- Daily volume45 ml
- 18 kg x 15 mg/kg = 270 mg
Frequently asked questions
Is this a substitute for a prescription?
No. It is an arithmetic aid; dosing decisions belong to a qualified prescriber.
What about maximum daily dose?
Check the product ceiling separately — weight-based maths can exceed it in larger patients.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.