BMI Calculator

Free online BMI calculator providing instant, accurate results based on WHO standards. Calculate your Body Mass Index and get personalized health insights.

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Note: BMI is a general indicator and may not be accurate for athletes, pregnant women, or the elderly. Consult a healthcare provider for a complete health assessment.

What is BMI?

Body Mass Index (BMI) is a widely used screening tool that helps assess body weight categories. It's calculated using your height and weight measurements and provides a reliable indicator of body fatness for most people.

The BMI formula used worldwide, as endorsed by the World Health Organization (WHO), is:BMI = weight(kg) / [height(m)]²

BMI Categories

Underweight

BMI: Below 18.5

May indicate nutritional deficiency or other health issues

Normal Weight

BMI: 18.5 - 24.9

Generally indicates optimal health status

Overweight

BMI: 25.0 - 29.9

May increase risk of health conditions

Obese

BMI: 30.0 or higher

Higher risk of various health complications

Note: While BMI is a useful screening tool, it's not a diagnostic measure. Factors such as age, gender, ethnicity, muscle mass, and body composition are not considered in BMI calculations.

For a complete health assessment, consult with healthcare professionals who can evaluate your BMI alongside other health indicators.

How to Use BMI Calculator

Enter Measurements

Input your height (cm) and weight (kg)

Auto Calculate

The system will automatically calculate your BMI

View Results

Understand your BMI range and health recommendations

Understanding Measurement Units

Height Units

Centimeters (cm)

Metric system, commonly used worldwide

Example: 170 cm = 1.7 meters

Feet (ft)

Imperial system, used in the US and UK

Example: 5'7" = 170 cm

Inches (in)

Imperial system, used with feet

Example: 67 inches = 170 cm

Weight Units

Kilograms (kg)

Metric system, standard unit worldwide

Example: 70 kg = 154 lbs

Pounds (lbs)

Imperial system, common in the US

Example: 154 lbs = 70 kg

Our BMI calculator automatically converts between different units for your convenience. Simply select your preferred units and enter your measurements.

BMI Calculator Examples

See how our BMI calculator handles different measurement units to provide consistent, accurate results

Using BMI Calculator with Metric Units

Height Input:

170 cm

Weight Input:

65 kg

BMI Result:

22.5

Normal weight

Our BMI calculator instantly converts your metric measurements (centimeters and kilograms) to calculate your BMI

BMI Calculator with Feet and Pounds

Height Input:

5'7"(170 cm)

Weight Input:

143 lbs(65 kg)

BMI Result:

22.5

Normal weight

The BMI calculator automatically converts imperial measurements to calculate accurate BMI results

BMI Calculator with Inches

Height Input:

67 inches(170 cm)

Weight Input:

143 lbs(65 kg)

BMI Result:

22.5

Normal weight

Use our BMI calculator with total inches for height - perfect for those who prefer imperial measurements

Our online BMI calculator makes it easy to calculate your Body Mass Index regardless of your preferred units. Try our BMI calculator now to get instant, accurate results with any combination of measurement units.

What Users Say About Our BMI Calculator

John D.

Fitness Enthusiast

"This BMI calculator is the most accurate tool I've found! I use it regularly to track my BMI and fitness progress. The instant results and detailed BMI recommendations are super helpful."
Posted on TrustPilot

Sarah M.

Personal Trainer

"As a trainer, I recommend this online BMI calculator to all my clients. It's the most reliable BMI measurement tool, easy to use, and provides clear health insights based on BMI ranges."
Posted on ProductReview

Robert K.

Healthcare Professional

"A professional BMI calculator that's both reliable and straightforward. I appreciate how it provides both metric and imperial measurements for BMI calculation. Perfect for quick assessments."
Posted on TrustPilot

Emily W.

Nutrition Coach

"This is my go-to BMI calculator for client consultations. The BMI charts are clear, calculations are instant, and the BMI-based health guidance is comprehensive."
Posted on Sitejabber

James H.

Weight Loss Journey

"Been using this free BMI calculator to track my progress. The BMI tracking feature is simple yet accurate, and helps me stay motivated with my health goals."
Posted on TrustPilot

Linda P.

Wellness Blogger

"The best online BMI calculator I've found! The BMI results are instant, and the health recommendations based on your BMI score are detailed and helpful. Highly recommend!"
Posted on ProductReview

BMI Calculator FAQ

What is BMI Calculator?

BMI (Body Mass Index) Calculator is a standardized tool that helps you calculate your body mass index using your height and weight. It's widely used by health professionals to assess whether a person has a healthy body weight.

How accurate is this BMI Calculator?

Our BMI Calculator uses the official formula endorsed by the World Health Organization (WHO) and other major health organizations. The calculation method is (weight in kg) / (height in meters)².

Is my data safe when using this calculator?

Absolutely. Our BMI calculator works entirely in your browser and doesn't store any personal information. Your height and weight measurements are only used for the immediate calculation and are never saved or transmitted to any server.

What do the BMI ranges mean?

According to WHO standards: Under 18.5 is Underweight, 18.5-24.9 is Normal weight, 25-29.9 is Overweight, and 30 or greater is Obese. However, BMI is just one indicator of health and should be interpreted alongside other factors.

Can I use this BMI Calculator for children?

This calculator is designed for adults aged 20 and older. For children and teens, please consult specific BMI-for-age calculators as they take into account age and gender differences in body composition.

How often should I check my BMI?

While you can check your BMI anytime, it's typically recommended to track it monthly if you're on a weight management program. Remember that BMI is just one measure of health and should be used alongside other health indicators.