Metric & imperial units
Toggle between kg/cm and lb/in. The calculator converts and computes BMI using the standard kg/m² formula.
BMI Calculator
Calculate BMI from height and weight in metric or imperial units.
- 100% free
- No sign-up
- Instant results
- Privacy-friendly
About the BMI Calculator
Calculate your Body Mass Index (BMI) instantly with this free BMI calculator. Enter height and weight in metric (kg/cm) or imperial (lb/in) units and see your BMI value plus category — underweight, healthy, overweight, or obese — with a clear visual indicator.
BMI is a simple screening measure based on weight relative to height (kg/m²). It is widely used for population health context, but it is not a medical diagnosis and may not reflect body composition for athletes, pregnant people, older adults, or children.
The BMI Calculator on The 360 Tools is free, private, and runs in your browser — no account or download required.
How to use the BMI Calculator
Enter height and weight, pick metric or imperial units, and get your BMI with category guidance in seconds.
- 1 Choose metric (kg and cm) or imperial (lb and in) units.
- 2 Enter your height and weight — results update as you type.
- 3 Read your BMI number and category on the visual range bar.
- 4 Use the result as a screening starting point; talk to a clinician for personal health advice.
Features of our BMI Calculator
A clean, accurate BMI check with unit switching and category guidance — built for quick personal use.
Instant BMI result
See your Body Mass Index update live as you adjust height or weight — no submit button needed.
Category guidance
Understand whether your BMI falls in underweight, healthy, overweight, or obese ranges used in common adult screening charts.
Visual range bar
A clear category bar helps you see where your result sits at a glance, not just as a raw number.
Honest screening context
Copy explains that BMI is a population tool, not a full health assessment — so you use the number wisely.
Free & private
No signup and no server storage. Height and weight stay in your browser session.
Who uses our BMI Calculator?
People who want a quick BMI check for wellness tracking, coaching, or education can use this free tool.
Individuals tracking wellness
Get a fast BMI snapshot between weigh-ins or when comparing metric and imperial measurements.
Fitness coaches & trainers
Show clients a simple screening number alongside other metrics like body fat or waist measurements.
Students & educators
Demonstrate the BMI formula and adult category ranges in health or PE classes.
HR & wellness programs
Point employees to a free, private calculator for optional self-checks without collecting data.
Parents (adult ranges)
Learn how adult BMI categories work — and remember child BMI uses different percentile charts.
Researchers & writers
Quickly verify example BMI values when explaining health content or building calculators.
Why use our BMI Calculator?
You need a trustworthy BMI number fast — with units that match how you measure, and categories that are easy to read.
- 01
Standard formula, clear result
BMI is computed the same way clinicians and charts expect: weight ÷ height², with unit conversion handled for you.
- 02
Switch units without math
Work in kg/cm or lb/in and stay focused on the result instead of converting by hand.
- 03
See the category, not just the number
The visual bar and labels make underweight / healthy / overweight / obese ranges obvious.
- 04
Private by default
No account and no upload — a screening tool that respects personal health data.
People also ask
What is a healthy BMI range?
For most adults, a BMI between 18.5 and 24.9 is considered healthy. Below 18.5 is underweight, 25 to 29.9 is overweight, and 30 or above is classified as obese. BMI is a screening measure, not a diagnosis.
How is BMI calculated?
BMI equals weight in kilograms divided by height in metres squared (kg/m²). The calculator also accepts imperial units and converts them for you.
Can I switch between metric and imperial units?
Yes. Toggle between kg/cm and lb/in. Results update instantly with your BMI value and category.
Is BMI accurate for everyone?
BMI is a simple population screening tool. It may not reflect body composition for athletes, pregnant people, older adults, or children. Use it as a starting point, not a medical diagnosis.
Is the BMI Calculator free to use?
Yes. The BMI Calculator is completely free with no sign-up, no hidden charges and no usage limits. All tools on The 360 Tools are free forever.
Is my data safe when using the BMI Calculator?
Yes. Your input is processed locally in your browser whenever possible and is never stored on our servers or shared with third parties.
Does the BMI Calculator work on mobile?
Yes. The BMI Calculator is built mobile-first and works on any modern phone, tablet or desktop browser without installing anything.
Embed this tool on your website
Add the free BMI Calculator to your own site or blog — copy the snippet below and paste it into your HTML. It's free for any website; we only ask that you keep the credit link.
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