Calculator
Body mass index (BMI) calculator
BMI is a single division: your weight divided by the square of your height in metres. The tool below does that, places the result in the World Health Organization's adult bands, and gives the weight range considered healthy for your height. No sign-up, and nothing you type reaches a server — the calculation runs in your browser.
Result
BMI
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WHO band
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Healthy range for your height
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This is a screening ratio, not a body composition measurement. BMI does not separate muscle from fat: someone training regularly can land in the "overweight" band while carrying low body fat, and the reverse holds too — the same BMI can describe low muscle mass and a high fat percentage. That is why Cookrange reads progress from the trend in your own record rather than from a single number.
The concepts: body recomposition,basal metabolic rate,maintenance calories.
World Health Organization adult BMI bands
| BMI | Classification |
|---|---|
| Under 18.5 | Underweight |
| 18.5 – 24.9 | Normal range |
| 25.0 – 29.9 | Overweight |
| 30.0 – 34.9 | Obesity (class I) |
| 35.0 – 39.9 | Obesity (class II) |
| 40.0 and above | Obesity (class III) |
What BMI measures, and what it does not
BMI is a ratio derived in the 19th century for population statistics, and that is still what it does best: screening large groups quickly. At the level of one person it cannot see three things. It does not separate muscle from fat. It does not know where fat sits on the body — waist circumference is more informative than BMI on that. And the same number means different things across bone structure, ethnicity, age and pregnancy.
The practical consequence: treat BMI as a starting point, not a verdict. If you are setting a target, a trend logged across weeks is more reliable than any single day's number, which is exactly what Cookrange's progress analytics reads.
Where the healthy weight range comes from
The tool above does not use a separate "ideal weight" formula. It applies the WHO's normal band of 18.5–24.9 to your own height: lower bound 18.5 × height², upper bound 24.9 × height². That choice is a matter of honesty. The "ideal weight" formulas in the literature (Devine, Robinson, Miller) disagree with each other by several kilograms and none of them is a WHO standard. Giving a range rather than a single number stays closer to what the data actually supports.
Common questions
Does Cookrange replace a dietitian or a doctor?
No. The health disclaimer in the Terms of Service is explicit: Cookrange is not a medical device and doesn’t provide medical advice, diagnosis, or treatment — the nutrition and training suggestions it generates are for general information and motivation only. If you have an existing health condition, are pregnant, or have a chronic illness, you should consult a health professional. Details on the Terms of Service.
Is Cookrange free?
Yes, the core of the app is free. Today’s free tier includes unlimited meal logging, gym check-in, squads, and long-term progress history. It also includes 2 generations a day through Cookrange AI — a shared pool covering plan regeneration, recipe generation, and chat. Premium raises that to 20 a day — see the exact price on the pricing page.
Cookrange is not a medical device or a health application and does not diagnose. If your BMI result worries you, speak to a doctor or a dietitian. The other tool:calorie and macro calculator.