Example 1
- 35 kg
- 140 cm
17.9
What child BMI at 35 kg and 140 cm? 17.9. That is BMI. Percentile waits for age 2-20 and the CDC table.
BMI percentile calculator
Type weight and height. 35 kg and 140 cm give 17.9. 40 kg and 150 cm give 17.8. 30 kg and 130 cm give 17.8. The main result is BMI. Percentile, z, and EER only with age 2-20 and the CDC table.
Not a clinic verdict and not a growth chart from a visit. The main result is BMI with one decimal place. Percentile does not run from the two fields alone.
Results
Enter data and click Calculate.
How it works
BMI for children in this calculator is weight in kg divided by height in metres squared. 35 / 1.40² = 17.857. The calculator writes 17.9 in the result. 40 kg and 150 cm give 17.8. 30 kg and 130 cm give 17.8. This is the same quotient as the BMI card.
Field a is weight. Field b is height. Age, months, sex, and activity do not enter 17.9. CDC percentile, LMS z-score, and the 5-85 band show only with age 2-20 and a loaded CDC_BMI_FOR_AGE_LMS table.
Without age or without the table, percentile, z, and range stay blank. IOM EER runs only at age 3-18. The 17.9, 17.8, and 17.8 examples leave age empty, so you keep BMI alone.
The BMI card next door has the same kg / m² for adults, with no CDC grid. The name mentions percentile, but the main number is BMI. That is not a development score by itself.
Type weight, type height, then Calculate. A comma in 35.5 parses. Zero height leaves a dash. A sketch from a quotient, not a doctor note and not a clinic chart.
35 kg and 140 cm give 17.9. 40 kg and 150 cm give 17.8. 30 kg and 130 cm give 17.8. With a US header, weight is pounds and height is inches.
Formula
BMI = weight[kg] / (height[m])²
How to use
- Type weight in kg, for example 35.
- Type height in cm, for example 140.
- Click Calculate. The result is 17.9.
- 40 kg and 150 cm give 17.8. 30 kg and 130 cm give 17.8.
- Percentile, z, and EER run only after age 2-20 and the CDC table. Or BMI on the BMI card.
35 kg and 140 cm = 17.9
BMI = kg / m². 35 and 140 give 17.9. Percentile only with CDC and age 2-20.
- BMI
- Weight over height squared. 35 kg and 140 cm show 17.9. This is not a percentile.
- percentile
- The CDC row. It runs at age 2-20 with the LMS table. 17.9 alone does not give it.
- CDC
- The LMS table on the page. Without it you keep 17.9. 40 kg and 150 cm also give 17.8 BMI.
Examples
Example 2
- 40 kg
- 150 cm
17.8
What BMI at 40 kg and 150 cm? 17.8. Same quotient, no percentile in this example.
Example 3
- 30 kg
- 130 cm
17.8
What BMI at 30 kg and 130 cm? 17.8. Another pair, the same 17.8.
Related calculators
Common questions
What BMI at 35 kg and 140 cm?
17.9. 35 / 1.40², then one decimal place in the result.
What about 40 kg and 150 cm?
17.8. The same quotient.
What about 30 kg and 130 cm?
17.8. Another pair, the same 17.8.
Is 17.9 a percentile?
No. The main result is BMI. CDC percentile only with age 2-20 and the LMS table.
When does z-score show?
With the percentile. You need age 2-20 and CDC_BMI_FOR_AGE_LMS. 17.9 alone does not compute it.
When does EER show?
At age 3-18 with IOM activity. Examples without age leave EER blank.
Is 17.9 a clinic score?
No. A sketch from a quotient. Not a growth chart and not a doctor note.
Does a comma in 35.5 work?
Yes. 35.5 and 35,5 are the same weight.
Does a US header change 35 and 140?
Yes. Then 35 is pounds and 140 is inches. The 17.9 examples are metric.
Knowledge sources
For children the calculator follows age-and-sex charts, not adult cut-offs.
Page updated in 2026.