BMI Calculator

Calculate your Body Mass Index instantly

Enter Your Details

Your BMI Result

Underweight
<18.5
Normal
18.5-24.9
Overweight
25-29.9
Obese
30+
Disclaimer: BMI is a general screening tool and not a diagnostic measure. Consult a healthcare professional for personalized advice.

BMI Categories

CategoryBMI Range
Severe Underweight< 16.0
Underweight16.0 - 18.4
Normal Weight18.5 - 24.9
Overweight25.0 - 29.9
Obese Class I30.0 - 34.9
Obese Class II35.0 - 39.9
Obese Class III≥ 40.0

How Does the BMI Calculator Work?

The Body Mass Index (BMI) calculator helps you assess whether your weight is in a healthy range for your height. It uses the standard formula: BMI = weight in kilograms divided by height in meters squared. Our tool supports both metric (kg, cm) and imperial (lbs, feet/inches) units with easy toggle switches.

After calculating your BMI, the tool shows a visual gauge indicating where you fall on the spectrum from underweight to obese. It also provides general health tips based on your category. BMI is widely used by health professionals as a quick screening tool, though it does not account for muscle mass, bone density, or body composition. For a complete health assessment, always consult with a qualified healthcare provider. This calculator is for informational purposes only and does not constitute medical advice.

Frequently Asked Questions

What is BMI?
BMI (Body Mass Index) is a measure of body fat based on height and weight. It is calculated as weight in kilograms divided by height in meters squared.
What is a healthy BMI range?
A healthy BMI is generally between 18.5 and 24.9. Below 18.5 is underweight, 25-29.9 is overweight, and 30+ is obese.
Is BMI accurate for everyone?
BMI is a general screening tool and may not be accurate for athletes, elderly, or pregnant women. It does not distinguish between muscle and fat mass.
How is BMI calculated?
BMI = weight (kg) / height (m) squared. For imperial: BMI = (weight in lbs x 703) / (height in inches squared).

Related Tools

What is BMI and how is it calculated?

BMI (Body Mass Index) is weight in kilograms divided by height in metres squared — BMI = kg ÷ m² — and is used as a quick screening measure for weight category, not as a diagnosis.

SnoopTool's BMI calculator accepts metric or imperial units and shows where you fall on the WHO categories. BMI ignores muscle mass and body composition, so athletes and older adults can be mis-categorised; treat it as one signal among several.

BMI Calculator: key facts

Reference facts for the SnoopTool BMI Calculator, a free browser-based tool.
Formula (metric)BMI = weight (kg) ÷ height (m)²
Formula (imperial)BMI = 703 × weight (lb) ÷ height (in)²
WHO categoriesUnderweight < 18.5 · Normal 18.5–24.9 · Overweight 25–29.9 · Obese ≥ 30
Asian-Indian cut-offsOverweight ≥ 23, obese ≥ 25 (per Indian consensus guidelines)
LimitationDoes not distinguish muscle from fat, or where fat is stored

Why use the SnoopTool BMI Calculator?

How to use the BMI Calculator (step by step)

  1. Choose your units. Select metric (kg/cm) or imperial (lb/ft-in).
  2. Enter height and weight. Type the two values.
  3. Read your BMI. The number and its WHO category appear immediately.
  4. Interpret with care. Use body fat percentage and waist measurement alongside BMI.

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