Calculators
BMI Calculator
Calculate Body Mass Index (BMI) from height and weight, and see the WHO adult category.
- Mobile Friendly
- Accessibility Tested
- Formula Verified
- SEO Optimized
- Fast Loading
- Responsive
Version 1.0.0 · Last reviewed
BMI Calculator
Enter height and weight. Results update live — calculation logic is unchanged.
Formula breakdown
Updates live as height and weight change.
- BMI = Weight / Height²
- 65 / (1.70 × 1.70)
- 65 / 2.8900
- 22.5
What-if simulator
Drag weight to preview BMI at 170 cm without changing your form inputs. Starting weight: 65 kg.
Result
Live output from your inputs
BMI: 22.5 · Normal weight
- BMI value
- 22.5
- BMI category
- Normal weight
- Healthy BMI range
- 18.5–24.9
- Ideal weight range
- 53.5–72
- Difference from healthy weight
- Within healthy weight range
- Health summary
- Your BMI is in the healthy range
kg/m²
WHO adult bands
kg/m²
kg
On track
Friendly overview
Health insights
Rule engineYour BMI is in the healthy range
A BMI of 22.5 falls in the commonly used healthy adult range. That is encouraging — and it is still worth pairing BMI with habits you can sustain.
Muscle, sleep, stress, and movement all shape how you feel day to day. BMI alone cannot capture those details.
Gentle habit ideas
- Keep a mix of cardio and strength work you enjoy
- Prioritize sleep and hydration as everyday foundations
- Revisit BMI occasionally rather than obsessing over daily swings
This is general wellness information for adults, not a medical diagnosis or personalized medical advice. BMI does not measure body fat, muscle, or overall health.
Next actions
BMR Calculator
Estimate resting calorie burn from age, sex, height, and weight.
Open tool
Daily Calorie Calculator
Explore daily energy needs with activity multipliers.
Open tool
Water Intake Calculator
Rough daily hydration targets based on body size and activity.
Coming soon
Protein Intake Calculator
Ballpark protein ranges for general wellness goals.
Coming soon
Body Fat Calculator
Estimate body-fat percentage when more detail than BMI helps.
Coming soon
How it worksShow guideHide guide
Introduction
The BMI calculator estimates Body Mass Index from height and weight using the standard adult formula. It is a screening tool, not a diagnosis of body fatness or health.
Disclaimer: This tool is for informational purposes only and is not professional medical, pharmaceutical, financial, or tax advice. Always verify doses with a licensed clinician or pharmacist.
Formula
Body Mass Index is body weight in kilograms divided by the square of height in meters.
- w — Weight in kilograms (kg)
- h — Height in meters (m)
- BMI — Body Mass Index in kg/m²
Step-by-step
- Enter your height in centimeters.
- Enter your weight in kilograms.
- Convert height to meters by dividing by 100.
- Square the height in meters.
- Divide weight by height squared to get BMI.
- Match the BMI value to an adult category band.
Worked example
For a person who is 170 cm tall and weighs 65 kg: height in meters is 1.70, height squared is 2.89, and BMI is 65 ÷ 2.89 ≈ 22.5 (Normal weight).
Use cases
- Quickly estimate BMI for personal tracking
- Compare results against WHO adult BMI categories
- Understand how height and weight interact in the BMI formula
Frequently asked questions
What is a healthy BMI range for adults?
For most adults, a BMI between 18.5 and 24.9 is classified as normal weight by WHO categories. Individual health needs can differ.
Is BMI accurate for athletes?
BMI does not distinguish muscle from fat, so muscular people may show a higher BMI without excess body fat. Use it as one signal among others.
Does this calculator work for children?
No. Child and teen BMI uses age- and sex-specific percentiles. This tool uses the adult BMI formula only.
What units does the calculator use?
Height is entered in centimeters and weight in kilograms. The result is expressed in kg/m².
Related tools
Popular tools
Calorie & Macro Calculator
Estimate daily calorie needs from BMR and activity, with a simple goal adjustment and macro split.
Average Calculator
Calculate the mean, sum, median, and range from a list of numbers.
Break-Even Calculator
Calculate the units and revenue needed to cover fixed and variable costs.
Was this helpful?
Your feedback stays on this device only — it is not sent to the Bestrao team yet.