Is BMI a perfect health metric?

No - it does not account for muscle mass or body composition.

What units are supported?

Metric (kg, cm) and Imperial (lb, ft/in).

BMI Calculator

Body Mass Index with category.

Weight (kg)Height (cm)

BMI

0.00

Understand your Body Mass Index

Enter your weight and height in either metric or imperial units to calculate BMI instantly. We convert imperial entries to metric behind the scenes so the formula is always weight (kg) / height (m)².

Standard BMI categories

< 18.5: Underweight
18.5 - 24.9: Normal
25 - 29.9: Overweight
30 and above: Obese

Tips for accurate values

Measure height without shoes and keep posture straight for a reliable reading.
Use the switcher in the calculator to toggle between metric and imperial at any time.
Copy your BMI result and category to share with doctors, coaches, or trainers.

Limitations

BMI is a screening tool, not a diagnostic. It does not distinguish muscle from fat and can misclassify athletes, seniors, or people with unique body compositions. Always pair BMI with other health indicators and professional advice.

Example calculations

70 kg & 175 cm → BMI ≈ 22.9 (Normal)
154 lb & 5'8" → converted to metric for the same 22.9 result

Explore more health tools

Track body changes over time with the Percentage Calculator.
Need age-based calculations? Use the Age Calculator for exact years and months.

FAQ

Do you store my information? No. All calculations run locally in your browser.

Is BMI enough to measure health? Use BMI as a quick checkpoint only. Consult a healthcare professional for personalised assessments.