What is a healthy BMI range for adults?

For many adults, BMI between 18.5 and 24.9 is often considered in the normal range.

How do I calculate BMI from kg and cm?

Convert height from cm to meters, then use BMI = weight in kg / (height in meters × height in meters).

Is BMI accurate for everyone?

BMI is a useful screening metric, but it does not measure body fat directly and may not fit athletes, children, or pregnancy contexts.

Is this BMI calculator free?

Yes. SmartFlexa BMI calculator is free and runs in your browser.

BMI Calculator Online Free | Check Body Mass Index

What is BMI?

Body Mass Index (BMI) is a number calculated from your weight and height. It is widely used as a quick screening tool for weight categories that may be linked to health risk, but it does not measure body fat directly and does not account for muscle, bone, or individual circumstances.

How to Calculate BMI

Weigh yourself in kilograms (kg).
Measure your height in meters (m), or centimeters (cm) ÷ 100.
Divide weight by height squared: BMI = kg ÷ m².
Compare the result to standard categories below.

BMI Categories

Underweight: BMI below 18.5
Normal: BMI 18.5 up to 25
Overweight: BMI 25 up to 30
Obese: BMI 30 or higher

Ranges follow common WHO-style cutoffs for adults. Children, athletes, and pregnancy need different assessments.

Example

Weight 70 kg, height 175 cm (1.75 m): BMI = 70 ÷ 1.75² ≈ 22.9, in the Normal range.

More BMI Examples

85 kg, 170 cm: BMI ≈ 29.4 (Overweight range)
52 kg, 165 cm: BMI ≈ 19.1 (Normal range)
95 kg, 180 cm: BMI ≈ 29.3 (Overweight range)

BMI Formula (kg and cm)

If your height is in centimeters, convert it first:m = cm / 100then compute:BMI = kg / m².

FAQ

What is a healthy BMI range for adults?: For many adults, BMI between 18.5 and 24.9 is commonly treated as the normal range. Use this as screening guidance, not a diagnosis.
How do I calculate BMI from kg and cm?: Convert cm to meters and then apply BMI = kg / m². Example: 175 cm = 1.75 m, so BMI = 70 / (1.75 × 1.75) ≈ 22.9.
Is BMI accurate for everyone?: No. BMI is useful at population level but can misclassify very muscular people and is not a full health assessment for children, pregnancy, or special conditions.
Is this tool free?: Yes. SmartFlexa’s BMI calculator is free with no signup.
Is my data secure?: Your weight and height stay in your browser; we do not send them to our servers for this calculation.

Explore Related Utility Tools

You can also tryJSON Formatter,Percentage Calculator, andUnit Converterfor related workflows.

BMI Calculator Online Free

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