在线免费BMI计算器
计算您的体重指数并了解您的体重类别。
Frequently Asked Questions
What is a normal BMI?
A BMI between 18.5 and 24.9 is considered normal/healthy weight. BMI under 18.5 is underweight, 25–29.9 is overweight, and 30 or above is obese.
How do I calculate BMI in kg and cm?
BMI formula (metric): BMI = weight (kg) ÷ height² (m²). Convert cm to m first by dividing by 100. For example, 70 kg at 175 cm: BMI = 70 ÷ (1.75 × 1.75) = 22.9.
What is the BMI formula for lbs and inches?
BMI formula (imperial): BMI = (weight in lbs × 703) ÷ height² (inches²). For example, 154 lbs at 69 inches: BMI = (154 × 703) ÷ (69²) = 22.7.
Is the BMI计算器 free to use?
Yes, the BMI计算器 on Allio Tools is completely free with no sign-up or registration required. It works directly in your browser.
How does the BMI计算器 work?
计算您的体重指数并了解您的体重类别。 No data is sent to a server — everything runs locally in your browser for maximum privacy and speed.
Do I need to install anything to use the BMI计算器?
No installation needed. The BMI计算器 runs entirely in your web browser on any device — desktop, tablet, or mobile.
Is my data safe when using the BMI计算器?
Completely safe. The BMI计算器 processes everything locally in your browser. No input data, results, or usage information is ever transmitted to or stored on any server.
Does the BMI计算器 work offline?
After the page loads for the first time, the BMI计算器 works without an internet connection for all client-side processing. Tools that fetch live external data (such as DNS or network lookups) require an active connection.
How accurate are the BMI计算器 calculations?
The BMI计算器 uses clinically validated formulas such as the Mifflin–St Jeor or Harris–Benedict equations where applicable. Results are population-based estimates and can differ from measured values by 10–20% for individuals with atypical body composition. See our Methodology page for full formula sources and references. Consult a qualified healthcare professional before making medical or dietary decisions.
Which formula does the BMI计算器 use?
The BMI计算器 uses an established, peer-reviewed formula endorsed by leading health organisations such as the WHO, CDC, or NIH where applicable. The specific formula is chosen for its validated accuracy across diverse adult populations under normal conditions.
Does the BMI计算器 work on all browsers?
Yes. The BMI计算器 is built with standard browser APIs and works on all modern browsers including Chrome, Firefox, Safari, and Edge — on both desktop and mobile. No plugins, extensions, or third-party software are required.
How do I save or export my results from the BMI计算器?
Select and copy the result text to paste into any document or app. For image tools, a Download button saves the file directly to your device. Your browser's built-in screenshot function also captures results quickly. No account or login is required.