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BMI

Body Mass Index from height and weight, metric or imperial.

Free to use, no sign-up required. BMI is one of 198 tools built into Xenition, alongside a chat that can use them for you.

Calculates Body Mass Index from your height and weight, places it in the adult WHO category, and shows the weight range that counts as healthy for your height.

How to use BMI

1. Choose Metric (cm and kg) or Imperial (inches and pounds).
2. Enter your Height and Weight. In Imperial, give your full height in inches, so 5 ft 10 in is 70.
3. Read your BMI, its category and where it sits on the coloured scale.
4. Check Healthy weight for your height for the weight range that gives a BMI of 18.5 to 24.9.

How it works

BMI = weight in kg ÷ (height in m)². Imperial inputs are converted with 1 in = 0.0254 m and 1 lb = 0.453592 kg. Categories: under 18.5 underweight, 18.5–24.9 healthy, 25–29.9 overweight, 30 and above obese.

Example

At 175 cm and 70 kg, BMI = 70 ÷ 1.75² = 22.9, in the healthy band. The healthy range for 175 cm is 56.7–76.3 kg. At 70 in and 180 lb, BMI is 25.8, just into overweight.

Questions about BMI

Why does my BMI say overweight when I am muscular?

BMI only compares weight with height. It cannot tell muscle from fat, so athletes with a lot of muscle often score as overweight. A waist measurement or body-fat estimate gives a better picture. BMI is an estimate, not a medical diagnosis.

Do these categories apply to children?

No. The bands here are the adult ones. Children and teenagers are assessed with age- and sex-specific percentile charts instead.

What it takes

• Height cm — Height in centimetres
• Weight kg — Body weight in kilograms

Use it from chat

You do not have to open BMI to use it. Ask Xenition in plain language and it runs the right tool, then carries the answer into whatever you are working on — a document, a spreadsheet, a deck.

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