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Japanese BMI Calculator (JASSO)Beta

Calculate your BMI from height and weight under the Japanese (JASSO) standard and see your obesity grade.

Result

Enter your height and weight to see your result.

How to use

Enter your height (cm) and weight (kg) to see your BMI and weight category under the Japanese (JASSO) standard. The bar under the result shows where you fall and the weight at each threshold for your height.

Japanese standard: JASSO

The Japan Society for the Study of Obesity (JASSO) defines obesity as excess fat accumulated in adipose tissue with a BMI of 25 or more. A BMI under 18.5 is underweight and 18.5 to under 25 is normal weight; obesity is graded as grade 1 (25 to under 30), grade 2 (30 to under 35), grade 3 (35 to under 40), and grade 4 (40 or more). There is no separate category for 23–24.9, so the normal-weight range is fairly wide.

Waist circumference and metabolic syndrome

In Japan, the waist circumference threshold used to diagnose metabolic syndrome is 85 cm or more for men and 90 cm or more for women, with a higher threshold for women. Metabolic syndrome means having visceral-fat obesity together with two or more of high blood glucose, high blood pressure, and abnormal blood lipids.

Things to keep in mind

In Japan, BMI is used only for adults; schoolchildren aged 6 to 18 are assessed with the obesity index (himando). Japan’s Ministry of Health, Labour and Welfare also notes that a BMI of 25 or more does not necessarily mean weight loss is medically required. It is important to look at waist circumference and overall health along with body weight.

Limits of BMI

BMI was designed as a quick way to gauge weight status across large populations. People with the same BMI can differ in health depending on muscle mass, fat distribution, age, and sex. Abdominal obesity in particular does not show up in BMI, so it is worth checking your waist circumference as well. Waist thresholds also differ by country, and the Notes section of the result shows the threshold for this standard. Results are for reference only and are not a medical diagnosis.

Sources

Frequently asked questions

At what BMI does obesity start under the Japanese standard?

At a BMI of 25. JASSO grades obesity as grade 1 (25 to under 30), grade 2 (30 to under 35), grade 3 (35 to under 40), and grade 4 (40 or more).

Does Japan have an overweight category?

No. Everything from 18.5 to under 25 counts as normal weight, and obesity grade 1 starts at 25. There is no separate category for 23–24.9.

Is BMI used for children too?

In Japan, BMI is used only for adults. Schoolchildren aged 6 to 18 are assessed with the obesity index (himando).