BMI Calculator
Body mass index with the healthy weight range for your height.
Enter your values
Choose one of: Metric (kg, cm), Imperial (lb, in).
Enter the weight you are working with.
Enter the height you are working with.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- BMI
- 25.1
- Category
- Overweight
- Healthy weight range
- 125.3 lb – 168.6 lb
- Distance from range
- 1.4 lb over
Working
- 1BMI = 77.1 kg ÷ (1.75 m)² = 25.1
Quick answer
Body mass index is weight in kilograms divided by height in metres squared; 18.5–24.9 is classed as a healthy range for most adults.
BMI = kg ÷ m²
At a glance
| What it does | Body mass index with the healthy weight range for your height. |
|---|---|
| Category | Health |
| Inputs needed | Units, Weight, Height |
| Main output | BMI |
| Formula | BMI = kg ÷ m² |
| Cost | Free — no sign-up, no download |
How to use the BMI Calculator
- 1Choose metric or imperial units.
- 2Enter your weight and height.
- 3Read your BMI and healthy range.
Inputs explained
- Units
- Choose one of: Metric (kg, cm), Imperial (lb, in).
- Weight
- Enter the weight you are working with.
- Height
- Enter the height you are working with.
Worked example
Using the values the calculator loads with:
Inputs
- UnitsImperial (lb, in)
- Weight170
- Height69
Results
- BMI25.1
- CategoryOverweight
- Healthy weight range125.3 lb – 168.6 lb
- Distance from range1.4 lb over
- BMI = 77.1 kg ÷ (1.75 m)² = 25.1
Frequently asked questions
Is BMI accurate for athletes?
No. Muscle is denser than fat, so muscular people often read as overweight despite low body fat. Use waist-to-height or body fat instead.
What BMI is healthy?
18.5 to 24.9 for most adults. Risk rises below 18.5 and above 25, though the cutoffs differ for some Asian populations.
What do I need to enter into the BMI Calculator?
Just 3 values: units, weight, height. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the BMI Calculator work out the answer?
Body mass index is weight in kilograms divided by height in metres squared; 18.5–24.9 is classed as a healthy range for most adults. It applies the formula BMI = kg ÷ m² and shows the working so you can check each step by hand.
Is the BMI Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.