How it works
The BMI calculator uses height and weight to estimate adult body mass index, then compares the result with standard adult BMI categories.
Body mass index
BMI Calculator online
Estimate adult BMI from height and weight, see your BMI category, compare healthy weight range, and continue into calorie planning.
Local calculation
No account or saved profile
Formula transparent
BMR, TDEE, BMI shown together
Next step ready
Macros, schedule, or explanation
BMI result
Step 2Ready
Your BMI result appears here.
Formula explanation
BMI equals weight in kilograms divided by height in meters squared. Healthy weight range is estimated from the adult BMI 18.5-24.9 reference range.
Related calculators
Quick Answers
What can BMI tell me?
BMI can place adult height and weight into a broad screening category.
It is useful as a quick starting point, especially when paired with a healthy weight range for your height.
What can BMI miss?
BMI does not measure body fat, muscle mass, waist size, or individual health status.
Athletes, older adults, and people with different body compositions can have the same BMI but different health contexts.
How does BMI fit into calorie planning?
BMI adds context, but calorie planning still depends on BMR, TDEE, goals, and real progress.
Use BMI as a screening signal, then estimate daily calories if you want a practical weight-loss, maintenance, or weight-gain plan.
Guides
FAQ
What is BMI?
BMI compares body weight with height. It is an adult screening estimate, not a diagnosis.
What is a healthy BMI range?
For adults, the standard healthy BMI range is 18.5 to below 25.
Does BMI work for children and teens?
Ages 2-19 need BMI-for-age percentile interpretation instead of fixed adult BMI categories.
Why can BMI be misleading for muscular people?
BMI does not separate muscle from fat, so muscular users can have a higher BMI without the same body composition.
Is this medical advice?
No. BMI results are educational screening estimates and are not medical advice.