What is the standard BMI formula?
The formula is BMI = Weight (kg) / [Height (m)]². For imperial units: BMI = 703 × Weight (lbs) / [Height (in)]².
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BMI Calculator - Calculate Body Mass Index | 1ClickTools
Calculate your Body Mass Index (BMI) and healthy weight range for adults and teens. Metric and Imperial units 100% free in browser.
About This Tool
Body Mass Index (BMI) is a standardized screening metric established by the World Health Organization (WHO) to classify adult body weight relative to height. It is widely used by healthcare professionals, personal trainers, and insurance providers to evaluate whether an individual is underweight, at a healthy weight, overweight, or obese. Our browser-native BMI Calculator supports both Imperial units (pounds and feet/inches) and Metric units (kilograms and centimeters). It uses the Quetelet formula (BMI = kg / m²) to compute your exact numerical score, pinpoints your weight bracket on a visual WHO color scale, and projects your ideal healthy weight range. Because all health metrics calculate locally within client-side browser memory using JavaScript, your age, weight, and personal health statistics remain 100% private and never touch remote servers.
Frequently Asked Questions
Is my personal weight or health data saved on a server?
No. 1ClickTools calculates BMI 100% locally in your browser memory.
What is considered a healthy adult BMI range?
According to the World Health Organization (WHO), a healthy adult BMI is between 18.5 and 24.9.
Does BMI distinguish between muscle mass and fat mass?
No. BMI is a general statistical proxy and does not directly measure muscle vs. fat body composition.
Can I calculate BMI for children and teens?
For children and teens (ages 2-19), BMI percentiles relative to age and gender growth charts are used.
Works on smartphone browsers?
Yes, fully responsive across mobile phones, tablets, and desktop computers.
How much weight do I need to lose to reach a normal BMI?
The calculator displays your personal weight delta needed to reach the 24.9 upper boundary.
Is any software installation required?
No, works directly inside standard web browsers.
Does it cost money to use?
No, 100% free with no limits.
Is 1ClickTools BMI Calculator free?
Yes, 100% free for personal wellness tracking.