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Dosage Calculator
Calculate a weight-based drug dose (mg/kg) and daily total from patient weight and frequency.
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Version 1.0.0 · Last reviewed
How it worksShow guide
Introduction
The dosage calculator multiplies patient weight by an ordered mg/kg dose to estimate a single dose and daily total. Use it to double-check weight-based prescribing — not as a substitute for a pharmacist or clinician.
Disclaimer: This tool is for informational purposes only and is not professional medical, pharmaceutical, financial, or tax advice. Always verify doses with a licensed clinician or pharmacist.
Formula
Weight-based dose equals patient weight times the ordered milligrams per kilogram. Multiply by doses per day for the daily total.
- w — Patient weight (kg)
- d_kg — Ordered dose (mg/kg)
Step-by-step
- Enter the patient weight in kilograms.
- Enter the ordered dose in mg per kg.
- Set how many times the dose is given per day.
Worked example
A 70 kg patient ordered 10 mg/kg twice daily receives 700 mg per dose and 1,400 mg per day.
Use cases
- Estimate a single weight-based dose in mg
- Convert mg/kg orders into a daily total
- Cross-check pediatric or critical-care dose math
Frequently asked questions
Does this replace a drug reference?
No. Always confirm the drug, indication, renal/hepatic adjustments, and max dose with a licensed professional and an official reference.
Can I enter pounds?
Convert pounds to kilograms first (lb ÷ 2.2046). This tool expects kilograms for SI dosing conventions.
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