Ibuprofen Dose Calculator for Children

This calculator works out a weight-based ibuprofen dose for children — the range in milligrams, the matching volume of liquid, how often it can be given and the maximum in 24 hours. Weight is a better guide than age for children’s medicines, because children of the same age can differ a lot in size.

How the dose is calculated

For fever and mild to moderate pain in children over 3 months, standard guidance is 5 to 10 mg of ibuprofen per kg of body weight per dose, given every 6 to 8 hours (three to four times a day), up to a maximum of 30 mg/kg in 24 hours.

• The range shown is 5 mg/kg to 10 mg/kg. The practical dose is the midpoint (7.5 mg/kg).
• A single dose is capped at 400 mg, and the daily total is capped at 30 mg/kg or 1,200 mg, whichever is lower.
• The volume is the dose divided by the concentration: mL = mg ÷ (mg per mL). A 100 mg/5 mL liquid contains 20 mg/mL; a 200 mg/5 mL liquid contains 40 mg/mL.

Age and weight limits

The calculator gives a dose only for children who are at least 3 months old and weigh at least 5 kg, and it stops at 40 kg, where adult dosing normally applies. Some countries advise waiting until 6 months, so always follow the guidance where you live. Under those limits, a doctor or pharmacist should advise on treatment.

Safe use

• Use the syringe or measure that comes with the medicine, not a kitchen spoon.
• Leave at least 6 hours between doses and never exceed the daily maximum.
• Check other medicines and “cold and flu” products for ibuprofen so it isn’t given twice.
• Children who are dehydrated, vomiting, or unwell with kidney, heart or stomach problems need advice before an NSAID is given.

Frequently asked questions

How much ibuprofen can I give a child?

The usual dose is 5–10 mg per kg of body weight every 6–8 hours, up to 30 mg/kg a day. Use the calculator for your child’s weight, and always check it against the label on your product.

How often can ibuprofen be given?

Every 6 to 8 hours, with no more than four doses in 24 hours.

What’s the difference between 100 mg/5 mL and 200 mg/5 mL liquid?

The same volume of the stronger liquid contains twice as much ibuprofen. If you switch bottles, recalculate the volume, because the same number of millilitres would double the dose.

Can I give ibuprofen and paracetamol together?

They work differently and are sometimes used alternately, but you should follow the advice of a doctor or pharmacist on timing and doses for each one.

When should I get medical advice?

If your child is under 3 months, has a fever lasting more than 3 days, seems very unwell, is drinking poorly or shows signs of dehydration, has a rash, or the pain isn’t settling.

Medical disclaimer

Sources & references

• Médecins Sans Frontières. Essential drugs: Ibuprofen oral. medicalguidelines.msf.org
• NICE. British National Formulary for Children (BNFc) — ibuprofen monograph. bnfc.nice.org.uk