calculatortools

BMI Calculator BMI 计算器

Calculates Body Mass Index with health category, supports metric and imperial units. 计算身体质量指数并给出健康区间，支持公制与英制单位。

BMI Calculator

Auto-calculate on input
Unit System
cm
kg
Height
ft
in
lb
Your BMI
0.0
Please enter height and weight
Underweight
< 18.5
Normal
18.5 – 23.9
Overweight
24.0 – 27.9
Obese
≥ 28.0

BMI Calculator Guide

BMI (Body Mass Index) is a value derived from dividing weight by the square of height, used to assess whether an individual's weight is within a healthy range. This tool references the Asian adult BMI standard. All calculations run locally in your browser — no data is uploaded.

Formula

Metric: BMI = Weight(kg) ÷ Height(m)²
Imperial: BMI = 703 × Weight(lb) ÷ Height(in)²

Health Ranges (Asian Standard)

  • Underweight: BMI < 18.5, may indicate risk of malnutrition.
  • Normal: BMI 18.5 – 23.9, weight is within a healthy range.
  • Overweight: BMI 24.0 – 27.9, risk of chronic diseases begins to rise.
  • Obese: BMI ≥ 28.0, weight management under medical guidance is recommended.

FAQ

Why does the Asian standard differ from the WHO standard?
Asian populations have a higher risk of type 2 diabetes and cardiovascular disease at the same BMI levels. Therefore, China, Japan, and the WHO Western Pacific Region have lowered the overweight threshold to 24 and the obesity threshold to 28, which better reflects Asian body types.
Is BMI accurate? What are its limitations?
BMI is calculated solely from height and weight and cannot distinguish between muscle and fat proportions. BMI may be less meaningful for athletes, pregnant or nursing women, the elderly, and individuals with edema. It is recommended to consider body fat percentage, waist circumference, and other indicators together.
Can children use this standard?
No. Children and adolescents are still growing, and BMI assessment requires comparison with age- and gender-specific percentile charts. This tool is only intended for adults aged 18 and above.

Note: Results from this tool are for reference only and do not constitute medical diagnosis or treatment advice.

BMI 计算器说明

BMI（Body Mass Index，身体质量指数）是用体重除以身高的平方得出的数值，用于衡量人体胖瘦程度。本工具参考亚洲成人 BMI 标准，所有计算在浏览器本地完成，不会上传任何数据。

计算公式

公制：BMI = 体重(kg) ÷ 身高(m)²
英制：BMI = 703 × 体重(lb) ÷ 身高(in)²

健康区间（亚洲标准）

  • 过轻：BMI < 18.5，可能存在营养不良风险。
  • 正常：BMI 18.5 – 23.9，体重处于健康范围。
  • 超重：BMI 24.0 – 27.9，慢性病风险开始升高。
  • 肥胖：BMI ≥ 28.0，建议在医生指导下进行体重管理。

常见问题

为什么亚洲标准和世界卫生组织（WHO）标准不一样？
亚洲人群在相同 BMI 下患 2 型糖尿病、心血管疾病的风险更高，因此中国、日本及 WHO 西太区将超重切点下调至 24，肥胖切点下调至 28，更符合亚洲人体质。
BMI 准确吗？有什么局限？
BMI 仅根据身高体重计算，无法区分肌肉与脂肪比例。运动员、孕妇、哺乳期女性、老年人及水肿患者的 BMI 参考价值有限，建议结合体脂率、腰围等指标综合判断。
儿童可以用这个标准吗？
不可以。儿童与青少年处于生长发育期，BMI 评估需对照同龄同性别百分位曲线图，本工具仅适用于 18 岁以上成人。

说明：本工具结果仅供参考，不构成医学诊断或治疗建议。