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BMI calculator

The BMI formula is your weight in kilograms divided by your height in metres squared: 70 kg at 1.75 m is 22.9. Enter your height and weight below for your number and the usual adult range it falls in.

Updated 21 October 2026. Sources named on the page.

Key factFor adults, a BMI of 18.5 to 24.9 is the World Health Organization's usual range, 25 to 29.9 is above it and 30 or more is well above; for 70 kg at 175 cm the BMI is 22.9.

Metric or imperial: kilograms and centimetres, or pounds, feet and inches
For adults aged 19 and over; the same formula and ranges for women and men
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Shows the formula, worked examples and what BMI cannot tell you

Calculate your BMI

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BMI is a screening number. It does not measure body fat, muscle or health, and it is for adults aged 19 and over. Not medical advice.

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The formula, the ranges and worked examples

BMI = weight in kilograms divided by height in metres squared. In pounds and inches the same number is 703 times weight in pounds, divided by height in inches squared.

Commonly used adult BMI ranges

BMI	Range
Below 18.5	Below the usual adult range
18.5 to 24.9	Within the usual adult range
25 to 29.9	Above the usual adult range
30 and over	Well above the usual adult range

Worked examples

Weight	Height	Working	BMI
70 kg	1.75 m	70 / (1.75 x 1.75)	22.9
95 kg	1.80 m	95 / (1.80 x 1.80)	29.3
50 kg	1.60 m	50 / (1.60 x 1.60)	19.5
154 lb	69 in (5 ft 9 in)	703 x 154 / (69 x 69)	22.7

BMI by height and weight (kg)

Height	50 kg	60 kg	70 kg	80 kg	90 kg	100 kg
1.50 m	22.2	26.7	31.1	35.6	40.0	44.4
1.55 m	20.8	25.0	29.1	33.3	37.5	41.6
1.60 m	19.5	23.4	27.3	31.2	35.2	39.1
1.65 m	18.4	22.0	25.7	29.4	33.1	36.7
1.70 m	17.3	20.8	24.2	27.7	31.1	34.6
1.75 m	16.3	19.6	22.9	26.1	29.4	32.7
1.80 m	15.4	18.5	21.6	24.7	27.8	30.9
1.85 m	14.6	17.5	20.5	23.4	26.3	29.2
1.90 m	13.9	16.6	19.4	22.2	24.9	27.7

Sources: The adult cut points of 18.5, 25 and 30 are the widely used World Health Organization adult ranges; CDC and NHS publish the same formula and ranges for adults

General information, not medical advice.

How to calculate BMI, step by step

Step one: measure your height in metres (175 cm is 1.75 m). Step two: multiply that number by itself (1.75 x 1.75 = 3.06). Step three: divide your weight in kilograms by that result (70 / 3.06 = 22.9). That is your BMI.

In pounds and inches the same number is 703 x weight in pounds, divided by height in inches squared.

What the number can and cannot tell you

BMI is a quick screening number that compares weight with height. It does not see muscle, bone, age or where weight sits on the body, so two people with the same BMI can look and be very different. For anything about your health, ask your doctor.

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Beyond one number

One reading says little; a line over weeks says more. The Daily Journal lets you log weight next to food, sleep and habits, so you can see what moves with what, and the first three habits are free.

Questions

What is BMI?

BMI, or body mass index, is your weight in kilograms divided by your height in metres squared. It is a quick screening number that compares weight with height.

What BMI range is usual for adults?

The commonly used adult ranges are below 18.5, 18.5 to 24.9, 25 to 29.9 and 30 or more. These ranges describe where a number sits; they do not say how healthy any one person is.

How do I calculate BMI in pounds and inches?

Multiply your weight in pounds by 703, then divide by your height in inches squared. For example 154 lb at 69 inches is 703 x 154 / (69 x 69), which is 22.7.

Is BMI different for women and men?

No. The adult formula and the ranges are the same for women and men, so this calculator asks for sex only as an option and does not change the result.

What does BMI not tell you?

BMI does not measure body fat, muscle, bone, where fat is carried, age or ethnicity, so it can mislead for very muscular people and others. It is for adults aged 19 and over, not for pregnancy or medical decisions. Talk to a doctor or an accredited practising dietitian about your own health.

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