Medication Dosage by Weight Calculator
Calculate the correct medication dosage based on body weight using mg/kg dosing.
Supports adults and children in metric and imperial units.
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Calculated Dosage
Weight-based dosing calculates medication amounts based on body weight, commonly used for children and certain adult medications.
Core formula:
Dose (mg) = Weight (kg) × Dose Rate (mg/kg)
For divided doses:
Dose per Administration = Total Daily Dose / Number of Doses per Day
Common medication dose rates (for reference):
| Medication | Typical Dose Rate | Frequency |
|---|---|---|
| Acetaminophen (children) | 10–15 mg/kg | Every 4–6 hours |
| Ibuprofen (children) | 5–10 mg/kg | Every 6–8 hours |
| Amoxicillin | 25–50 mg/kg/day | Divided 2–3 times |
Unit conversions:
- Weight: 1 lb = 0.4536 kg | 1 kg = 2.205 lbs
- Volume: 1 tsp = 5 mL | 1 tbsp = 15 mL
Important safety notes:
- Always verify dosing with a pharmacist or physician
- Never exceed the maximum recommended dose
- This calculator is for educational purposes only
- Individual medical conditions may require dose adjustments
- Always use the concentration printed on YOUR medication label