Home·Body Metrics

BMI Calculator

BMI is weight divided by height in metres squared. The Asia-Pacific cut-offs treat 23 as overweight and 25 as obese — lower than the WHO international values of 25 and 30.

Your numbers

BMI

23.5

Ideal weight

63.6kg

What it means

A BMI of 23.5 is overweight by the Asia-Pacific classification.

Formula

BMI = Weight (kg) ÷ (Height (cm) ÷ 100)²

BMI cannot tell muscle from fat, so it reads high for people who train heavily.

What to enter

InputDefaultAccepted range
Height (cm)Height in centimetres; converted to metres inside the formula.17050 ~ 250
Weight (kg)The second weight you are comparing against.6810 ~ 300

Step by step

FormulaBMI = Weight (kg) ÷ (Height (cm) ÷ 100)²
With the default numbersBMI = 68 ÷ (170 ÷ 100)²
AnswerBMI = 23.5

Quick reference table

Results when only Height (cm) changes and everything else stays put.

Height (cm)BMIIdeal weight (kg)
8594.115.9
12841.536
17023.563.6
25010.9137.5

What each result means

ResultAt default values
BMIA build index from height and weight alone; it cannot tell muscle from fat.23.5
Ideal weight (kg)A reference weight from height alone — a benchmark, not a goal.63.6

Common mistakes

BMI cannot tell muscle from fat, so it reads high for people who train heavily.

Glossary

Height (cm)
Height in centimetres; converted to metres inside the formula.
Weight (kg)
The second weight you are comparing against.
BMI
A build index from height and weight alone; it cannot tell muscle from fat.
Ideal weight
A reference weight from height alone — a benchmark, not a goal.

Frequently asked questions

Q. How is BMI Calculator calculated?

BMI = Weight (kg) ÷ (Height (cm) ÷ 100)² — BMI is weight divided by height in metres squared. The Asia-Pacific cut-offs treat 23 as overweight and 25 as obese — lower than the WHO international values of 25 and 30.

Q. Can you walk through an example?

With Height (cm) 170, Weight (kg) 68, the answer is BMI 23.5.

Q. What do I need to enter?

Enter Height (cm), Weight (kg). The result recalculates as you type, and an empty box counts as zero.

Q. How much does the answer move if I change a number?

Changing only Height (cm) moves the answer to Height (cm) 85 → BMI 94.1 and Height (cm) 250 → BMI 10.9. The table below lays out five steps.

Q. How are the numbers rounded?

Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.

Q. Anything to watch out for?

BMI cannot tell muscle from fat, so it reads high for people who train heavily.

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These calculators help you understand health figures; they do not replace diagnosis or prescription. See a clinician if you have symptoms.