How is BMI calculated?

Divide weight in kilograms by height in meters squared. At 170 cm and 65 kg, BMI is 65 ÷ 1.7² ≈ 22.5; feet, inches and pounds are converted first.

Is a BMI of 23 overweight?

Only under the Asia-Pacific bands, where 23 to 24.9 is overweight (at risk). Under the WHO international bands, 18.5 to 24.9 is normal.

Is a BMI of 25 obese?

Not under WHO, where 25 to 29.9 is overweight (pre-obese) and obesity starts at 30. Under the Asia-Pacific bands, 25 is the start of obese class I.

What is the formula for BMR?

Mifflin–St Jeor: 10 × weight (kg) + 6.25 × height (cm) − 5 × age, plus 5 for men or minus 161 for women. For a 30-year-old woman at 165 cm and 60 kg that is about 1,320 kcal a day.

What is the difference between BMR and TDEE?

BMR is the energy used at rest; TDEE multiplies it by your activity level. A BMR of 1,320 kcal times 1.53 is about 2,020 kcal a day.

Does it tell me how many calories to eat to lose weight?

No. It shows only an estimate of daily energy expenditure and never sets an intake or weight-loss target. For an eating plan, talk to a doctor or a registered dietitian.

What is a healthy weight for 5 ft 8 in?

Under the WHO bands, BMI 18.5 to 24.9 at 5 ft 8 in is 121.5 to 164.0 lb. Under the Asia-Pacific bands the upper limit is 150.8 lb.

Is BMI accurate if I am muscular?

Not very. BMI cannot tell muscle from fat, so a muscular person can fall in the overweight or obese band with little body fat.

Can I use this BMI calculator for kids or teens?

No. Adult bands do not apply under 19; children and teens are assessed with BMI-for-age growth percentiles by sex.

BMI Calculator with BMR & TDEE

Free BMI calculator with WHO and Asian cut-offs, plus a BMR calculator (Mifflin–St Jeor and Harris–Benedict) and TDEE estimate of calories burned per day.

Loading the tool…

This BMI calculator shows your body mass index and its band from height and weight, then adds age and sex to estimate basal metabolic rate (BMR) and daily energy expenditure, often called TDEE, on the same screen. You can switch between the WHO international and the Asia-Pacific BMI cut-offs, and BMR is shown with both the Mifflin–St Jeor and the revised Harris–Benedict equations. It also turns the normal BMI band into a weight range for your height, in kg or lb. Results are estimates for reference, not a diagnosis or a weight goal.

How to use

Under "Units", choose "cm · kg" or "ft · in · lb". Switching converts the height and weight you already entered.
Enter "Height" and "Weight". With "ft · in · lb" you fill in "Height (feet)" and "Height (inches)" separately.
Enter "Age" and "Sex"; both are used for BMR.
Pick the closest option under "Usual activity level".
Under "BMI classification" choose "WHO international" or "Asia-Pacific", and under "BMR formula" choose "Mifflin–St Jeor" or "Harris–Benedict (revised)". The results update at once.
Read "Body mass index (BMI)" with its band bar, the normal-weight range, "Estimated basal metabolic rate", "Same with the other formula" and "Estimated daily energy expenditure". Open "Formulas and sources" for the equations and references.

How it works

BMI = weight (kg) ÷ height (m)², and the band is read from the value rounded to one decimal. A BMI of 24.96, for example, counts as 25.0 and falls in the WHO overweight band.
The bands are for adults aged 19 and older. With an age under 19 the adult band and the normal-weight range are not shown.
BMI and BMR are estimates from height, weight, age and sex only; muscle mass, body shape, pregnancy and breastfeeding are not taken into account. The result is not a diagnosis and does not suggest a weight goal or calorie intake.
Results are calculated for heights from 50 to 250 cm and weights from 10 to 400 kg.
Everything runs in the browser and nothing is uploaded. Your entries are saved in this browser on this device, so they are still there next time.

How to calculate BMI, and WHO vs Asian BMI cut-offs

BMI is weight divided by height in meters squared; with pounds and inches the page converts to kilograms and centimeters first. Someone 5 ft 8 in tall who weighs 150 lb has a BMI of about 22.8. The WHO international bands are under 18.5 underweight, 18.5 to 24.9 normal, 25 to 29.9 overweight and 30 or more obese. The Asia-Pacific bands keep 18.5 but treat 23 to 24.9 as overweight (at risk) and 25 or more as obese.

The same person can land in different bands. At 175 cm and 75 kg the BMI is about 24.5, which is normal under WHO but overweight (at risk) under the Asia-Pacific scheme. The lower Asian cut-offs were proposed by the WHO Western Pacific Region in 2000, based on reports that health risks rise at a lower BMI in Asian populations. National bodies sometimes add steps or revise their thresholds, so check your own country's current guidance.

BMR formula: Mifflin–St Jeor vs Harris–Benedict

Mifflin–St Jeor (1990) is 10 × weight (kg) + 6.25 × height (cm) − 5 × age, plus 5 for men or minus 161 for women. The revised Harris–Benedict equation recalculated the 1919 original in 1984; for men it is 88.362 + 13.397 × weight + 4.799 × height − 5.677 × age. For a 35-year-old man at 175 cm and 75 kg, Mifflin–St Jeor gives about 1,674 kcal a day and Harris–Benedict about 1,734 kcal.

That gap of about 60 kcal shows that BMR equations are population averages, not measurements. Two people with the same height and weight can differ, especially if one carries more muscle. That is why the page shows the other formula's result next to the one you chose.

TDEE calculator: estimating calories burned per day

Daily energy expenditure is estimated as BMR × physical activity level (PAL). The FAO/WHO/UNU report groups lifestyles as sedentary or light (1.40 to 1.69), active or moderately active (1.70 to 1.99) and vigorously active (2.00 to 2.40). Multiplying the 1,674 kcal above by the light-activity example value 1.53 gives about 2,561 kcal, and the whole light range gives about 2,343 to 2,829 kcal.

This is an estimate of what the body uses, not an amount to eat. The normal-weight range is likewise just the normal BMI band expressed as weight. At 5 ft 8 in it is 121.5 to 164.0 lb under WHO, and the Asia-Pacific upper limit is 150.8 lb.

Questions and answers

How is BMI calculated?: Divide weight in kilograms by height in meters squared. At 170 cm and 65 kg, BMI is 65 ÷ 1.7² ≈ 22.5; feet, inches and pounds are converted first.
Is a BMI of 23 overweight?: Only under the Asia-Pacific bands, where 23 to 24.9 is overweight (at risk). Under the WHO international bands, 18.5 to 24.9 is normal.
Is a BMI of 25 obese?: Not under WHO, where 25 to 29.9 is overweight (pre-obese) and obesity starts at 30. Under the Asia-Pacific bands, 25 is the start of obese class I.
What is the formula for BMR?: Mifflin–St Jeor: 10 × weight (kg) + 6.25 × height (cm) − 5 × age, plus 5 for men or minus 161 for women. For a 30-year-old woman at 165 cm and 60 kg that is about 1,320 kcal a day.
What is the difference between BMR and TDEE?: BMR is the energy used at rest; TDEE multiplies it by your activity level. A BMR of 1,320 kcal times 1.53 is about 2,020 kcal a day.
Does it tell me how many calories to eat to lose weight?: No. It shows only an estimate of daily energy expenditure and never sets an intake or weight-loss target. For an eating plan, talk to a doctor or a registered dietitian.
What is a healthy weight for 5 ft 8 in?: Under the WHO bands, BMI 18.5 to 24.9 at 5 ft 8 in is 121.5 to 164.0 lb. Under the Asia-Pacific bands the upper limit is 150.8 lb.
Is BMI accurate if I am muscular?: Not very. BMI cannot tell muscle from fat, so a muscular person can fall in the overweight or obese band with little body fat.
Can I use this BMI calculator for kids or teens?: No. Adult bands do not apply under 19; children and teens are assessed with BMI-for-age growth percentiles by sex.