Enter your child’s weight and age, and get the exact weight-based dose of Tylenol or Motrin in the right mL or pills for every common concentration. Built by a pediatric nurse practitioner — for the parent standing in the kitchen at 11 PM.
Before you use this: this calculator is educational and assumes an accurate weight. It is not medical advice and does not replace your pediatrician. Double-check the dose against the label on your bottle before giving any medicine, and call your clinician if you’re unsure. If your child has kidney, liver, bleeding, or chronic health conditions, confirm with your provider before using either medicine.
⚠️ Before you dose: match your bottle’s concentration
This is the step I walk every parent through in person, because it’s the dosing mistake I see most often. Different bottles of the same medicine can have totally different concentrations — and giving the dose for the wrong concentration can be twice or half the intended amount.
Look at the front of your medicine bottle, usually toward the bottom of the label.
Find the line that shows the concentration — it’ll read something like “160 mg per 5 mL” or “50 mg per 1.25 mL.” For pills, it’ll show the strength per tablet, like “100 mg chewable” or “200 mg.”
Match that exact concentration to one of the rows in the dosing chart below. Use that row’s dose — ignore the others.
If you can’t find the concentration on your bottle, or yours doesn’t match any row below, don’t guess. Call your pediatrician or pharmacist.
The fine print
Acetaminophen (Tylenol) is dosed at 15 mg/kg per dose, every 4–6 hours as needed. Do not exceed 5 total doses of acetaminophen (including all forms) in 24 hours.
Ibuprofen (Motrin/Advil) is dosed at 10 mg/kg per dose, every 6 hours as needed. Do not exceed 4 total doses of ibuprofen (including all forms) in 24 hours. Not for use in infants under 6 months.
Ibuprofen generally works better for fever and musculoskeletal pain than acetaminophen. Consider ibuprofen first (if 6+ months), and save acetaminophen for breakthrough between ibuprofen doses if needed.
Pill forms are only appropriate for children who can reliably chew or swallow them without risk of choking.
Any fever in a baby under 3 months (100.4°F / 38.0°C or higher) is an ER-level concern. Go directly to the ER — do not treat at home.
This tool does not replace a medical evaluation. Call your clinician or 911 if your child has trouble breathing, is unresponsive, has a first-ever seizure, has a stiff neck, or has a rash that doesn’t blanch when pressed.