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Kids BMI calculator (HPB BMI-for-age, 6 to 18)
Enter your child's age, height and weight. You get the BMI and the same weight band HPB's charts give, the charts schools in Singapore use.
HPB BMI-for-age cut-offs, ages 6 to 18. Sources read on 5 Nov 2026.
Result
The HPB bands
HPB grades children aged 6 to 18 by BMI-for-age percentile, against Singapore school children measured in 2002: severely underweight below the 3rd percentile, underweight from the 3rd to below the 5th, acceptable from the 5th to below the 90th, overweight from the 90th to below the 97th, and severely overweight from the 97th. Schools measure every pupil's height and weight twice a year against this chart, MOE says.
HPB prints the cut-offs by whole year of age only, so a child of 9 years and 11 months uses the row for 9. HPB publishes no cut-offs under age 6.
Why another site might give a different answer
Most BMI calculators use the US CDC bands (overweight from the 85th percentile, obese from the 95th) or the WHO 2007 reference. One HealthHub question-and-answer page uses the CDC numbers too. HPB's own table, MOE's 2026 reply on overweight pupils and MOH's 2022 reply all use 90th and 97th, so that is what this calculator follows.
Questions parents ask
What BMI is healthy for a child in Singapore?
HPB counts a BMI between the 5th and the 90th percentile for the child's age and sex as acceptable. For an 8-year-old boy that is a BMI of 13.7 to 20.9; for an 8-year-old girl, 13.5 to 20.1.
Why does the school say overweight when another calculator says healthy?
Schools use HPB's chart, where overweight starts at the 90th percentile of Singapore children measured in 2002. US calculators use the CDC chart, built on different children, with overweight from the 85th.
Can I use this for a child under 6?
No. HPB publishes BMI cut-offs from age 6. For younger children the doctor plots BMI on the chart in the Child Health Booklet.
Sources
- HPB: Healthy Weight Healthy Children booklet, BMI-for-Age Percentiles (6-18 Years), 2015 (read 5 Nov 2026)
- HealthHub: Know the difference between the BMI of adults and children (read 5 Nov 2026)
- MOE parliamentary reply: Height and weight of students (4 Jan 2021) (read 5 Nov 2026)
- MOE parliamentary reply: Overweight students and weight management (26 Feb 2026) (read 5 Nov 2026)
- HealthHub: My child is in the 75th percentile in terms of BMI (read 5 Nov 2026)
