Acetaminophen vs Ibuprofen for Kids: What Parents Should Know
Acetaminophen (Tylenol) and ibuprofen (Motrin or Advil) are both used for fever and pain, but they are not interchangeable. The right choice depends on your child's age, weight, symptoms, hydration, medical history, and the exact formulation in your hand.
The Perfect Dose calculator supports acetaminophen for children 2 months and older once they weigh at least about 15 lb, and ibuprofen for children 6 months and older. Always check the active ingredient and concentration on the bottle, follow the label or your clinician's instructions, and review the full Perfect Dose medical disclaimer before using a calculator.
Acetaminophen and ibuprofen at a glance
When each medicine may fit
Both medicines can reduce fever and relieve pain from a minor illness, teething, or an injury when used for an eligible child. Acetaminophen is the option supported by the calculator for younger infants. Ibuprofen is for children at least 6 months old and is best given with food or milk when possible.
Use the correct bottle and dose window
The calculator uses acetaminophen at 15 mg/kg with a 650 mg per-dose cap, 4–6 hours between doses, and no more than 5 doses in 24 hours. It uses ibuprofen at 10 mg/kg with a 400 mg per-dose cap, 6–8 hours between doses, and no more than 4 doses in 24 hours. The preselected liquid formulations are acetaminophen 160 mg / 5 mL and Children's ibuprofen 100 mg / 5 mL.
Calculate an acetaminophen dose
Calculate a children's ibuprofen dose
Parent FAQ
When should a parent consider acetaminophen versus ibuprofen for a child?
Acetaminophen (Tylenol) and ibuprofen (Motrin or Advil) can both reduce fever and relieve pain in eligible children, such as discomfort from a minor illness, teething, or an injury. Acetaminophen is the option supported by the calculator for younger infants, while ibuprofen may be useful for children who are at least 6 months old and can take it with food or milk. Choose based on the child's age, symptoms, hydration, medical history, and the exact product, and follow the label or a clinician's instructions rather than treating the medicines as interchangeable.
What are the minimum age and weight boundaries for acetaminophen and ibuprofen?
The Perfect Dose calculator supports acetaminophen for children 2 months and older once they weigh at least about 15 lb (about 7 kg), and supports ibuprofen for children 6 months and older. Younger or smaller infants should not be given the corresponding medicine without direct guidance from a clinician, regardless of weight. The calculator enforces the medication age boundaries, but a clinician's judgment always overrides a dosing chart.
How do acetaminophen and ibuprofen doses, intervals, and maximum doses differ?
The calculator uses acetaminophen at 15 mg per kilogram, capped at 650 mg per dose, with 4–6 hours between doses and no more than 5 doses in 24 hours. It uses ibuprofen at 10 mg per kilogram, capped at 400 mg per dose, with 6–8 hours between doses and no more than 4 doses in 24 hours. These formulas apply to acetaminophen liquid 160 mg / 5 mL and Children's ibuprofen liquid 100 mg / 5 mL. Doses are based on current weight, so confirm the bottle concentration and never repeat a dose early.
What formulation and duplicate-ingredient checks matter with these medicines?
Check the active ingredient and concentration on the bottle every time, and use an accurate measuring device. The preselected Perfect Dose flows use acetaminophen liquid 160 mg / 5 mL and Children's ibuprofen liquid 100 mg / 5 mL. Do not give two products with the same active ingredient, including acetaminophen in some cough, cold, or combination medicines or ibuprofen in another pain or fever product. Ask a pharmacist or clinician if you are unsure which product is safe.
Should ibuprofen be given with food or milk, and does acetaminophen need food?
Ibuprofen can irritate the stomach, so give it with food or milk when possible, especially for older children who are not actively eating. Acetaminophen does not need to be given with food in the way ibuprofen often does. If a child is vomiting, dehydrated, unable to drink, or has a medical condition that changes medication safety, contact a clinician before choosing a medicine.
When should a parent contact a clinician, Poison Control, or emergency services?
Contact a clinician when you are unsure which medicine fits the symptom, your child is younger than the applicable age or weight boundary, symptoms are severe or worsening, or fever or pain persists. If you suspect a wrong dose or possible poisoning, contact Poison Control at 1-800-222-1222 in the United States. For trouble breathing, swelling of the face, lips, or tongue, a seizure, severe or unusual drowsiness, unresponsiveness, severe dehydration, or another emergency, call 911 or your local emergency services immediately. A clinician's judgment always overrides a dosing chart.
Related child dosage guides
This page is educational guidance, not a substitute for medical care. Review the medical disclaimer, and contact a clinician when your child's symptoms do not fit routine over-the-counter care.