What does BMI Calculator do?

Body mass index and optional body fat percentage. Output is an indicative estimate for 2026—not legal, tax, or financial advice. Verify with official rules and a professional if needed.

Do I need to sign up?

No account is required. The calculator runs in your browser for quick estimates; always double-check for contracts or tax filings in 2026.

How accurate is the result?

It depends on your inputs and the model’s assumptions. Use it for planning and what-if analysis; for binding decisions, confirm numbers from primary sources and advisers.

Is my data stored on the server?

Results are not meant to be posted publicly; some tools may use local device storage (see the tool’s on-page copy).

BMI calculator

Body mass index from weight and height, with WHO adult category bands.

Weight (kg)

Height (cm)

Enter weight and height, then calculate.

Methodology

BMI = weight(kg) / height(m)²
Categories: underweight <18.5 · normal <25 · overweight <30 · obese ≥30

Example

70 kg · 175 cm → BMI ≈ 22.9 (normal).

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