Dosage
Calculate the correct medication dosage using weight-based dosing (mg/kg). Free online dosage calculator with frequency scheduling and liquid medicine concentration conversion to mL.
About This Calculator
The Dosage Calculator helps patients, caregivers, and healthcare professionals determine the correct dose of medication based on body weight. Weight-based dosing is the standard for many drugs including antibiotics, pain relievers, anticonvulsants, and pediatric medications. Simply enter the patient's weight, the prescribed mg/kg dose, and the dosing frequency to get accurate results instantly.
The calculation follows the standard formula: Dose (mg) = Weight (kg) × Dosage (mg/kg). For liquid medications, the calculator also converts the required dose from milligrams to milliliters using the medicine's concentration (mg/mL). The total daily dose is computed by multiplying the single dose by the number of doses per day.
Regional Notes
India: Weight-based dosing is widely used in Indian hospitals and clinics for pediatric and critical care medications. Always verify the prescribed mg/kg dose from the treating physician.
United States: The FDA recommends weight-based dosing for many pediatric drugs. Use weight in kilograms (1 kg = 2.205 lbs). Common liquid concentrations are expressed in mg/mL.
United Kingdom: The NHS and BNF for Children provide weight-based dosing guidelines for most paediatric medications. Always double-check with a pharmacist.
This tool is for informational purposes only and does not replace professional medical advice. Always consult a doctor or pharmacist before administering any medication.
Frequently Asked Questions
How do I calculate medication dosage by weight?
Multiply the patient's weight in kilograms by the prescribed dosage in mg per kg. For example, a 70 kg patient prescribed 5 mg/kg would receive 70 x 5 = 350 mg per dose.
How do I convert mg to mL for liquid medication?
Divide the required dose in mg by the medicine concentration in mg/mL. For example, if you need 350 mg and the medicine has a concentration of 100 mg/mL, you need 350 / 100 = 3.5 mL.
What is the difference between dose and dosage?
A dose is the amount of medication taken at one time (e.g. 350 mg). Dosage includes the dose plus the frequency and duration (e.g. 350 mg three times daily for 7 days).
Is this dosage calculator suitable for pediatric patients?
Yes, this calculator works for patients of any age. Pediatric dosing is often weight-based (mg/kg), making this tool especially useful for children. Always consult a doctor before administering medication to children.
Can I use this calculator for both solid tablets and liquid medicine?
Yes. For tablets, use the dose in mg directly. For liquid medicine, enter the concentration in mg/mL to get the equivalent liquid dose in mL. This is essential for syrups, suspensions, and injectable medications.
How do I calculate the total daily dose?
Multiply the single dose by the number of times you take the medication per day. For example, 350 mg taken three times daily equals a total daily dose of 350 x 3 = 1,050 mg per day.