BMI Calculator

About BMI Calculator

BMI Calculator estimates your Body Mass Index from your height and weight and shows which standard category it falls in. It's a quick, private way to get a general read on weight relative to height — useful as a starting point, not a diagnosis.

Calculate your Body Mass Index Use BMI Calculator online for Fitness tasks with quick examples and copy-ready results.

How to use BMI Calculator

1. Open BMI Calculator on AltFTool — it loads instantly in your browser.
2. Enter the values you already know.
3. Adjust the options for your scenario.
4. Use the calculated result for comparison or planning.

Why use BMI Calculator

• Metric & imperial

  Enter height/weight in cm/kg or ft/in/lb.

• Instant category

  See the standard underweight / normal / overweight bands.

• Educational context

  Understand what BMI can and can't tell you.

Common use cases

• Get a quick BMI reading before a fitness or health check-in.
• Compare BMI in metric or imperial units.
• Track changes in BMI over time as a rough trend.

Frequently asked questions

Is BMI an accurate measure of health?

BMI is a general screening tool, not a diagnosis. It doesn't account for muscle mass, age, or body composition, so treat it as one data point and consult a professional for advice.

Which units can I use?

Both metric (cm, kg) and imperial (ft/in, lb) are supported.

Does it store my data?

No — your height and weight stay in your browser.