Children's Ibuprofen Dose Calculator
Weight based children's ibuprofen dose in mg and mL with daily max.
What it does
Children's ibuprofen dosing runs on weight, never age. A 20 kg child needs twice the milligrams of a 10 kg child, and the 100 mg per 5 mL suspension turns that math into milliliters parents can measure. Getting it right matters because too little leaves pain while too much risks kidneys and stomach.
The tool above computes 10 mg per kg per dose with a 400 mg cap. Enter weight in kg or lb. It returns the mg dose, the mL of standard suspension, and the daily max at 40 mg per kg. Defaults of 20 kg open solved at 200 mg with 10 mL.
Fever dosing splits by thermometer while pain dosing does not. Below 102.5 F, 5 mg per kg calms fever as well as 10; at or above, 10 works longer, holding about 8 hours against 6. Pain relief always uses 10 mg per kg every 6 to 8 hours.
The daily ceiling deserves respect. Forty milligrams per kg per day allows four full doses, and the page totals it so multi dose days stay legal. Alternating with acetaminophen on a schedule shows no proven comfort gain in AAP review and doubles error chances, so treat with one drug at a time.
Use the table for common weights, then dose the child. Shake the bottle, measure with the syringe not a spoon, and redose by the clock only while symptoms persist.
How to use
- Pick metric (kg) or imperial (lb).
- Enter the child's current weight.
- Read the mg dose first, then mL.
- Give every 6 to 8 hours as needed.
- Track the daily max across all doses.
- Call the doctor for under 6 months.
Formula
- Weight
- Body weight: kg in metric mode, lb converted inside in imperial.
- 10 mg/kg
- 10 mg per kg per dose.
- 20 mg/mL
- 100 mg per 5 mL suspension strength.
- Daily max
- 40 mg per kg per 24 hours.
Children's suspension at 100 mg per 5 mL, which is 20 mg per mL. Pain dosing at 10 mg per kg every 6 to 8 hours; fever dosing is 5 mg per kg under 102.5 F and 10 at or above. Maximum 40 mg per kg per day. For 6 months and older; younger infants need direct medical dosing.
Worked example
Example: 20 kg child, pain
A 20 kg child needs ibuprofen for pain. Find the dose in mg and mL.
- Dose: 10 mg x 20 kg = 200 mg.
- Liquid: 200 / 20 = 10 mL of 100 mg per 5 mL.
- Interval: every 6 to 8 hours as needed.
- Daily max: 40 mg x 20 kg = 800 mg.
- That is 4 doses of 200 mg in 24 hours.
- Imperial mirror: 44 lb gives 199.6 mg with 10 mL.
Reference table
| Weight | Dose | Liquid | Daily max |
|---|---|---|---|
| 10 kg | 100 mg | 5 mL | 400 mg |
| 20 kg (worked) | 200 mg | 10 mL | 800 mg |
| 30 kg | 300 mg | 15 mL | 1200 mg |
| 44 lb (imperial) | 199.6 mg | 10 mL | 798 mg |
Limits
- 6 months and older; younger needs the doctor.
- Standard 100 mg/5 mL only; drops differ.
- Fever bands need a thermometer reading.
- Weight, not age, drives every number.
Common mistakes
- Dosing by age instead of weight.
- Using kitchen spoons for mL.
- Stacking ibuprofen with other NSAIDs.
- Redosing early when fever lingers.
- Missing the 400 mg single cap.
Try it yourself
Quick checks. Answers sit tucked under each question.
44 lb child in imperial mode?
19.96 kg x 10 = 199.6 mg. Liquid 199.6 / 20 = 10 mL. Daily 19.96 x 40 = 798 mg.
90 kg teen (cap case)?
90 x 10 = 900, capped at 400 mg. Liquid 400 / 20 = 20 mL. Daily 90 x 40 = 3600 mg.
Tiny 5 kg infant weight?
5 x 10 = 50 mg with 2.5 mL, daily max 200 mg. Confirm age over 6 months first.
Questions
What is the standard dose?
10 mg per kg every 6 to 8 hours for pain. Fever under 102.5 F uses 5 mg per kg; at or above uses 10. Daily max is 40 mg per kg.
What concentration does the page assume?
100 mg per 5 mL, so 20 mg per mL. Divide the mg dose by 20 for mL. Infant drops at 50 mg per 1.25 mL match the same 40 mg per mL.
From what age?
6 months and older. Under 6 months, dosing needs the doctor directly.
Why does 44 lb match 20 kg?
44 lb is 20.0 kg, so 199.6 mg with 10 mL and 798 mg daily max. Same child, same answer.
Is there a single dose cap?
400 mg single dose. Heavy children hit the adult cap before the weight math does; the page applies it.
Should I alternate with acetaminophen?
No evidence of better comfort, with more dosing error risk per AAP review. Treat with one, dose it right, and watch comfort instead.
Sources
- DailyMed: ibuprofen suspension label, 5 and 10 mg/kg dosing
- AAP HealthyChildren: ibuprofen dosing table for fever and pain