Calculator
BMI Calculator
Calculate body mass index from height and weight using metric or imperial units.
Result
BMI
24.3
Screening category
Healthy range
Categories are general screening ranges.
How to use this calculator
What this calculator does
Calculate body mass index from height and weight using metric or imperial units.
How to use it
Choose your unit system, enter your weight and height, then review your BMI result and screening category.
What the result means
Use the result as a general reference point. Health estimates can vary by body composition, routine, age, and medical context.
Browse more health calculators for related estimates and comparisons.
Health results are broad educational estimates. They are not a diagnosis and should not replace advice from a qualified clinician.
Scenario guidance
When to use this
Use this when you want a quick body mass index estimate from height and weight for general educational context.
Example scenario
A person is tracking basic wellness measurements over time and wants a simple BMI reference point before discussing goals with a clinician.
Inputs that usually matter most
- Unit system, because metric and imperial inputs are entered differently.
- Weight, because BMI is directly proportional to the weight entered.
- Total height, because height is squared in the formula and strongly affects the result.
Common mistake to avoid
Do not treat BMI as a diagnosis or a direct measure of body fat, fitness, or individual health status.
How to interpret the result
Use the result as a broad screening-style reference. BMI categories can be useful for population-level context, but they do not account for muscle mass, body composition, pregnancy, age, ethnicity, or individual medical history.
Results are general educational estimates. This calculator does not diagnose, treat, or assess any health condition.
Formula
BMI is calculated internally with metric units as weight in kilograms divided by height in metres squared. Imperial inputs are converted from pounds, feet, and inches before calculation.
Example BMI
A person who weighs 77 kg and is 178 cm tall has a BMI of about 24.3. The equivalent imperial inputs produce nearly the same result.
Frequently Asked Questions
Can I use metric units?
Yes. Choose Metric and enter weight in kilograms and height in centimetres.
Is BMI accurate for everyone?
No. BMI does not directly measure body fat and may be less useful for athletes, older adults, and some body types.
Should BMI guide medical decisions?
Use BMI as a starting point and discuss health questions with a qualified clinician.