BMI Calculator

Calculate your body mass index and understand the result category.

BMI details

Enter height and weight. Age and sex are optional context only.

Example: 175 cm

Example: 70 kg

BMI is a screening measure, not a diagnosis. Adult BMI ranges may not apply to children, pregnancy, athletes, or people with specific medical conditions.

BMI result dashboard

BMI screening summary

Metric units

BMI score

22.9

Body Mass Index from your height and weight.

BMI category

Healthy weight

Common adult screening category, not a diagnosis.

Healthy BMI range

18.5 to 24.9

Common adult healthy weight BMI range.

Healthy weight range

56.7 kg to 76.3 kg

Approximate range for the entered height.

Height

175 cm

Converted automatically when switching units.

Weight

70 kg

Current weight used in the BMI formula.

Export

Save or share this BMI result

Copy the summary, copy the formula, download a CSV, or print a compact result.

Health context

Uses the standard adult BMI formula. BMI is useful for broad screening, but it does not directly measure body fat or replace professional medical advice.

Interpretation

What this BMI result means

Current category

Your BMI is 22.9, which is commonly classified as healthy weight for adults.

Height-based range

For your height, the common adult healthy BMI range corresponds roughly to 56.7 kg to 76.3 kg. Your entered weight is within the common adult healthy BMI range for this height.

What BMI leaves out

BMI does not account for muscle mass, body composition, age, ethnicity, pregnancy, or medical history.

Use health context

Consider professional advice if you have health concerns, unexplained weight change, pregnancy, or a medical condition.

Ranges

Adult BMI category ranges

Underweight

Below 18.5

Healthy weight

18.5 to 24.9

Overweight

25 to 29.9

Obesity

30 or higher

Formula

BMI formula explanation

Example using your inputs: 70 ÷ 1.75² = 22.9. Height is squared because BMI compares weight against body size rather than height alone.

Metric BMI

BMI = weight in kg ÷ height in meters²

Metric uses kilograms and meters.

Imperial BMI

BMI = 703 × weight in pounds ÷ height in inches²

Imperial uses pounds and total inches with the 703 conversion factor.

BMI basics

How to understand BMI

Body Mass Index

BMI compares body weight with height and returns a single screening number.

Adult categories

The categories help group results, but they are not medical diagnoses.

Height matters

Taller and shorter bodies are compared by squaring height in the formula.

Clinical context

A clinician may consider waist size, body composition, history, and other measures.

Limitations

Limitations of BMI

BMI is useful, but it should not be treated as a complete health assessment.

Muscle mass

A muscular build can raise BMI without indicating higher body fat.

Body composition

BMI does not show fat percentage, lean mass, or fat distribution.

Personal context

Age, sex, ethnicity, pregnancy, and medical history can matter.

Clinical limits

BMI should not replace medical advice or a full health assessment.

Next steps

Healthy next steps

Use multiple signals

Review BMI alongside waist measurement, fitness, sleep, diet, medical history, and how you feel.

Sustainable habits

Focus on steady, realistic habits rather than treating one number as a complete health picture.

Ask a professional

Seek professional advice for unexplained weight change or before major diet or exercise changes.

Trust

About this BMI estimate

Formula based

Uses the standard adult BMI formulas for metric and imperial units.

Private by design

Inputs are calculated in the browser. Do not enter sensitive personal information you do not want to use here.

Screening only

BMI categories are broad reference ranges and are not a diagnosis or treatment recommendation.

FAQ

BMI calculator questions

BMI stands for Body Mass Index. It compares weight with height and is commonly used as a broad adult screening measure for weight categories.