Health / Browser calculator

BMI Calculator

BMI Calculator works from the inputs you provide and returns bmi (kg/m²), adult screening range. Use the calculation panel to explore a scenario, then check the formula and limitations before applying the result.

Your inputs

Minimum: 1e-06 · Maximum: 1500
Minimum: 1e-06 · Maximum: 300
Minimum: 20 · Maximum: 120

Your results

Enter your values and calculate to see the result.

This calculator is for informational purposes only and is not a substitute for professional medical advice.

Formula and calculation method

BMI = weight in kilograms / [height in meters]².

Adult screening measure for age 20 and older. BMI does not measure body composition or diagnose health. Adult ranges should not be applied to children or pregnancy.

How to use bmi calculator

  1. Set Measurement system by choosing the option that matches your calculation.
  2. Set Weight (kg or lb). The example below uses 70.
  3. Set Height (cm or inches). The example below uses 175.
  4. Set Age (years). The example below uses 30.
  5. Select Calculate to update the result. Reset restores the illustrated inputs. Copy, print or download your own result if you need a record.

Worked example

At 70 kg and 175 cm, BMI is approximately 22.86 kg/m².

Example inputs
Measurement system
Metric (kg, cm)
Weight (kg or lb)
70
Height (cm or inches)
175
Age (years)
30
BMI (kg/m²)
22.85714286
Adult screening range
Within adult reference range

Factors affecting your result

Adult screening measure for age 20 and older. BMI does not measure body composition or diagnose health. Adult ranges should not be applied to children or pregnancy.

Changing measurement system changes the scenario being evaluated. Adjust one input at a time when comparing results, keep a copy of the assumptions, and compare values using the same unit and period. A precise arithmetic result does not make an uncertain assumption precise.

Frequently asked questions

How does the bmi calculator work?

BMI = weight in kilograms / [height in meters]².

What inputs does BMI Calculator need?

Enter measurement system, weight (kg or lb), height (cm or inches), age (years). Choose values that correspond to the same situation and measurement convention.

How should I interpret the bmi calculator result?

Adult screening measure for age 20 and older. BMI does not measure body composition or diagnose health. Adult ranges should not be applied to children or pregnancy.

Are my bmi calculator inputs uploaded?

No. The calculation runs in this browser. Favorites, recent tool names, theme and formatting preferences may be saved locally, but calculation inputs are not sent to a calculation server or stored by this website. Shared links do not include entered values.

Method reference

Maintained by Calculators.buzz Editorial Team. Implementation date: . No professional credentials or clinical review are claimed. Read our methodology policy.