BMI Calculator

Enter your height and weight in metric or imperial units to see your body mass index, the category it falls in and the weight range that counts as normal for your height. Nothing you type is stored.

Height

Weight

Your BMI

22.9

Category: Normal weight

A BMI between 18.5 and 24.9 is in the normal range. At your height that is about 56.7 to 76.3 kg.

What BMI is

Body mass index (BMI) compares your weight with your height. It is your weight in kilograms divided by your height in metres squared. Doctors and public-health bodies use it as a quick screening number for groups of adults, because it is easy to work out and needs no equipment.

BMI categories for adults

BMI	Category
Below 18.5	Underweight
18.5 to 24.9	Normal weight
25 to 29.9	Overweight
30 to 34.9	Obesity (class I)
35 to 39.9	Obesity (class II)
40 or more	Obesity (class III)

BMI formula in kilograms and in pounds

Metric: BMI = weight in kg ÷ (height in m × height in m). Example: 70 kg at 1.75 m is 70 ÷ 3.0625 = 22.9.
Imperial: BMI = 703 × weight in pounds ÷ (height in inches × height in inches). Example: 154 lb at 5 ft 6 in (66 inches) is 703 × 154 ÷ 4,356 = 24.9.
In Excel or Google Sheets, with kg in A1 and metres in B1, use =A1/(B1^2).

Normal weight range by height

A BMI from 18.5 to 24.9 is the normal range for adults. This table shows the weights that fall in that range at common heights.

Height	In feet and inches	Normal weight (kg)	Normal weight (lb)
150 cm	4 ft 11 in	41.6 to 56.0 kg	92 to 124 lb
155 cm	5 ft 1 in	44.4 to 59.8 kg	98 to 132 lb
160 cm	5 ft 3 in	47.4 to 63.7 kg	104 to 141 lb
165 cm	5 ft 5 in	50.4 to 67.8 kg	111 to 149 lb
170 cm	5 ft 7 in	53.5 to 72.0 kg	118 to 159 lb
175 cm	5 ft 9 in	56.7 to 76.3 kg	125 to 168 lb
180 cm	5 ft 11 in	59.9 to 80.7 kg	132 to 178 lb
185 cm	6 ft 1 in	63.3 to 85.2 kg	140 to 188 lb
190 cm	6 ft 3 in	66.8 to 89.9 kg	147 to 198 lb

BMI for children, older adults and different backgrounds

Children and teenagers (2 to 19): the adult categories do not apply. Their BMI is compared with growth charts for the same age and sex, and the result is a percentile, which a doctor or nurse can work out.
Adults of every age use the same cut-offs, but in older adults a BMI a little above the normal range is not always a concern, and unplanned weight loss can matter more than the number.
People of South, East and Southeast Asian background: the World Health Organization notes that health risks can start at a lower BMI than in other groups, so some health authorities use lower action points (often 23 and 27.5). Ask your doctor which applies to you.
Athletes and people with a lot of muscle can have a high BMI with a low amount of body fat.
During pregnancy BMI is only used from the weight before pregnancy.

What BMI cannot tell you

It does not tell muscle from fat, so very muscular people can score as overweight.
It ignores where fat is carried on the body, which matters for health.
Ranges can fit people of different ages, sexes and backgrounds differently.
It is not used for children and teenagers, who use age and sex based growth charts.
A single number is never a diagnosis. Blood tests, waist size and family history matter too.

How to use your result

Treat BMI as a starting point for a conversation with a doctor or dietitian, not as a verdict. The calculator also shows the weight range that counts as normal at your height, which is often more useful than the number alone.

How to use the BMI Calculator tool

Choose Metric (cm and kg) or Imperial (feet, inches and pounds).
Enter your height and your weight.
Read your BMI, the category and the colour scale with your position marked.
See the weight range that is normal for your height underneath.

Frequently asked questions

How is BMI calculated?

BMI is your weight in kilograms divided by your height in metres squared. A person who weighs 70 kg and is 1.75 m tall has a BMI of 70 ÷ (1.75 × 1.75) = 22.9.

What is a healthy BMI?

For adults, the World Health Organization treats 18.5 to 24.9 as the normal range, under 18.5 as underweight, 25 to 29.9 as overweight and 30 or more as obesity.

Is BMI accurate for everyone?

No. BMI is a quick screening number. It does not separate muscle from fat, and it does not take age, sex or body build into account. Athletes can have a high BMI without excess fat. It is not suitable for children, who use age-based charts.

How do I calculate BMI in pounds and inches?

Multiply your weight in pounds by 703, then divide by your height in inches squared. A person who weighs 154 pounds and is 5 ft 6 in (66 inches) tall has a BMI of 703 × 154 ÷ 4,356 = 24.9.

What is a normal weight for my height?

A BMI from 18.5 to 24.9 is the normal range. At 170 cm (5 ft 7 in) that is about 53.5 to 72.0 kg (118 to 159 lb), and at 180 cm (5 ft 11 in) it is about 59.9 to 80.7 kg (132 to 178 lb). The table on this page lists more heights, and the calculator shows the range for yours.

Does this calculator give medical advice?

No. It is general information only. For advice about your weight or health, talk to a doctor or other qualified health professional.

What is a healthy BMI for a woman, a man or an older adult?

The adult ranges are the same for women and men and for all adult ages: 18.5 to 24.9 is the normal range. Body fat differs between sexes and changes with age, so a doctor may read the same number differently for different people.

Can I use BMI for a child or teenager?

Not with the adult categories. For ages 2 to 19, BMI is compared with growth charts for the same age and sex and shown as a percentile. Ask a doctor or nurse, or use the growth chart tools from the CDC or WHO.

Last reviewed: October 22, 2026. Sources: CDC: Adult BMI categories, WHO: Obesity and overweight.