How to Calculate BMI for Age
What is BMI for Age?
BMI-for-age (also called BMI percentile) is used to assess weight status in children and adolescents aged 2–19. Because children grow rapidly and have different amounts of body fat at different ages, a standard adult BMI cut-off is inappropriate. Instead, BMI is compared to age- and sex-specific reference populations.
Step-by-Step Guide
- 1BMI is calculated the same way as for adults: kg / m²
- 2The result is then plotted on CDC or WHO growth charts to get a percentile
- 3< 5th percentile = Underweight
- 45th–84th percentile = Healthy weight
- 585th–94th percentile = Overweight
- 6≥ 95th percentile = Obese
Worked Examples
Frequently Asked Questions
What is Bmi Age Calc?
BMI-for-age (also called BMI percentile) is used to assess weight status in children and adolescents aged 2–19. Because children grow rapidly and have different amounts of body fat at different ages, a standard adult BMI cut-off is inappropriate
How accurate is the Bmi Age Calc calculator?
The calculator uses the standard published formula for bmi age calc. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.
What units does the Bmi Age Calc calculator use?
This calculator works with kilograms, inches, square metres, watts. You can enter values in the units shown — the calculator handles all conversions internally.
What formula does the Bmi Age Calc calculator use?
The core formula is: < 5th percentile = Underweight. Each step in the calculation is shown so you can verify the result manually.
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