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BMI Calculator

Calculate body mass index (BMI) to gauge weight relative to height.

Results

BMI
22.86

How to use this calculator

  1. Enter weight in kilograms.
  2. Enter height in centimeters.
  3. We convert height to meters, compute BMI, and display the result.

Inputs explained

Weight
Body weight in kilograms (convert from lbs: lbs ÷ 2.20462).
Height
Height in centimeters (convert from inches: in × 2.54).

How it works

BMI = weight (kg) ÷ height^2 (meters). Enter metric values for best accuracy; convert if needed before input.

Compare the BMI result with WHO categories (underweight, normal, overweight, obese) for general guidance.

Formula

BMI = weight_kg ÷ (height_m)^2

When to use it

  • Quick health screening for general BMI categories.
  • Tracking BMI changes over time alongside other metrics.
  • Converting doctor’s height/weight readings into BMI for forms or apps.

Tips & cautions

  • Use metric inputs for accuracy; convert from imperial before entering.
  • BMI is a screening tool—athletes or muscular individuals may have high BMI without excess fat.
  • Pair BMI with waist circumference or body fat estimates for a fuller picture.
  • Does not account for body composition or fat distribution.
  • Standard adult formula; not tailored for children, athletes, or certain populations.

Worked examples

70 kg, 175 cm

  • Height in meters = 1.75
  • BMI = 70 / 1.75^2 ≈ 22.86

90 kg, 165 cm

  • BMI ≈ 33.06
  • Falls in the obese category per WHO guidelines.

Deep dive

This BMI calculator uses the WHO formula (kg/m²) to show body mass index from weight and height. Enter weight in kg and height in cm to get your BMI instantly.

Use it as a quick screening tool, but remember BMI doesn’t capture muscle vs fat—combine it with other health metrics for better insight.

FAQs

Does BMI account for muscle mass?
No. Highly muscular individuals may show elevated BMI despite low body fat. Use other metrics for more detail.
Should BMI guide medical decisions?
Always discuss health decisions with your physician. BMI is a screening tool, not a diagnosis.

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BMI is an informational metric only. Consult healthcare providers for personalized health assessments.