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BMI Calculator

Calculate body mass index and category, metric or imperial.

bmi-calculator.local
Body mass index
Enter your weight and height to see your BMI.

Overview

Calculates your Body Mass Index (BMI), a quick screening number that relates your weight to your height. It is widely used as a first-pass indicator of whether your weight sits in a typical range for your height. It is a screening estimate, not a diagnosis.

How it works

BMI is your weight divided by the square of your height. In metric units, BMI equals weight in kilograms divided by height in meters squared. In imperial units, BMI equals 703 times weight in pounds, divided by height in inches squared. The common categories are: below 18.5 underweight, 18.5 to 24.9 normal range, 25 to 29.9 overweight, and 30 or above in the obese range. BMI does not measure body fat directly and does not account for muscle mass, so it is a starting point rather than a complete picture of health.

How to use it

  1. Choose your units (metric or imperial).
  2. Enter your height.
  3. Enter your weight.
  4. Read your BMI and the range it falls into.

Examples

Standard calculation

A person who is 170 cm and 70 kg has a BMI of 70 divided by 1.70 squared, which is 70 divided by 2.89, or about 24.2. That sits in the normal range.

Imperial calculation

A person who is 5 ft 8 in (68 in) and 160 lb has a BMI of 703 times 160, divided by 68 squared, which is about 24.3.

FAQ

Is BMI an accurate measure of health?
It is a useful screening tool, but it does not distinguish muscle from fat or show where fat is stored, so a healthy, muscular person can read high. Use it alongside other measures.
What is a normal BMI range?
The commonly used normal range is 18.5 to 24.9, though what is healthy for an individual depends on many factors.
Does BMI work for athletes?
Less well. People with high muscle mass often have a high BMI despite low body fat, because muscle weighs more than fat for its size.
Does it use the same formula for everyone?
The formula is the same for all adults. It is not designed for children, who use age and sex-specific percentile charts instead.
Is my data sent anywhere?
No. The calculation runs in your browser, so your inputs stay on your device.

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Embed this tool

Paste this snippet to put the tool on your own site. It runs entirely in the visitor's browser, the same as it does here.

<iframe src="https://tooldok.com/embed/bmi-calculator/" title="BMI Calculator by Tooldok" width="100%" height="560" style="border:1px solid #16130d;border-radius:16px;max-width:720px" loading="lazy"></iframe> <p style="font:13px sans-serif"><a href="https://tooldok.com/tools/bmi-calculator/" target="_blank" rel="noopener">BMI Calculator</a> by <a href="https://tooldok.com/" target="_blank" rel="noopener">Tooldok</a></p>