mg/kg → mL dose converter
Convert a pediatric weight-based dose (mg/kg) into a liquid volume (mL) using the medication concentration on the label.
To convert a pediatric mg/kg order to mL, multiply the ordered mg/kg dose by the child's weight in kg, then divide that mg amount by the liquid concentration in mg/mL. If the order is written as mg/kg/day, divide by the number of daily doses before converting to mL per dose.
Clinical disclaimer
Use actual weight in kilograms (not an estimate).
If your order is in mg/kg/day, convert to mg/kg/dose first.
Helps compute mg/day and mL/day totals for safety checks.
mg/kg to mL conversion workflow
Use the converter when the ordered dose and bottle concentration are already known. If you are still choosing the drug, dose range, frequency, or maximum dose, start with a medication-specific calculator instead.
- Confirm the order is mg/kg/dose or convert mg/kg/day into mg/kg/dose first.
- Use the child's current weight in kilograms, not pounds, unless you convert the weight first.
- Read the medication label concentration as mg per mL, or convert mg per 5 mL into mg/mL before entering it.
- Calculate the mL per dose, then compare the result with medication-specific maximum dose guidance.
- Round only after the full calculation, using the measuring device and local protocol for that medication.
Formula
To convert a pediatric mg/kg order to mL, multiply the ordered mg/kg dose by the child's weight in kg, then divide that mg amount by the liquid concentration in mg/mL. If the order is written as mg/kg/day, divide by the number of daily doses before converting to mL per dose.
- mg per dose = (mg/kg) × weight (kg)
- mL per dose = (mg per dose) ÷ concentration (mg/mL)
Tip: if you only know a daily dose (mg/kg/day), convert to mg/kg/dose first by dividing by doses per day.
Worked example
A child weighs 20 kg. The prescribed dose is 10 mg/kg. The bottle concentration is 40 mg/mL.
- mg per dose = 10 × 20 = 200 mg
- mL per dose = 200 ÷ 40 = 5 mL
Safety notes
- Verify you are using the correct units (kg, mg/kg, mg/mL).
- Double-check concentration: liquids commonly come in multiple strengths.
- Confirm frequency and max daily dose using medication-specific guidance.
- Use an appropriate measuring device (oral syringe preferred for small volumes).
Related pediatric dosing tools
For medication-specific dosing, max-dose checks, or common OTC liquid strengths, use a dedicated dosing tool before using this generic concentration converter.
Frequently asked questions
First compute mg per dose = (mg/kg) × weight (kg). Then compute mL per dose = (mg per dose) ÷ concentration (mg/mL). Always verify concentration on the label.
Convert to mg/kg per dose by dividing by the number of doses per day, then run the mg/kg → mL conversion. For example, 30 mg/kg/day divided BID (2 doses/day) = 15 mg/kg/dose.
Rounding depends on the medication, the formulation, and what measuring device is used (oral syringe vs cup). Many outpatient liquid meds are rounded to the nearest 0.1 mL, but always follow your local protocol.
No. This is a generic conversion tool. Medication-specific calculators incorporate max dose limits, age restrictions, indications, and formulations.