BMI Calculator

Weight isn’t the only indicator of health — a taller individual may weigh more than a shorter individual without it being an issue. Body Mass Index (BMI) combines weight and height to produce a single number that helps estimate whether a person’s weight is in a typical range for their height. This calculator provides your BMI, weight category, and an estimated healthy weight range instantly, and the calculation runs locally in your browser without sending or storing your data.

How to use the BMI Calculator

1. Select between metric (kg and cm) and imperial (lb and in) units.

   

2. Enter your weight and height using the selected unit system.

   

3. View your result: BMI value, weight classification and healthy range of weight for the height you entered.

   

4. Click Clear to reset the fields and start a new calculation.

   

What is BMI?

BMI is calculated by dividing weight by height squared. Because height is included in the formula, two people with the same weight but different heights can have different BMI values.

1. BMI formula: BMI = weight (kg) / height (m)². Example: a person weighing 75 kg at 1.77 m tall → 75 ÷ (1.77 × 1.77) ≈ 23.9.
2. Imperial formula: BMI = (weight (lb) ÷ height (in)²) × 703. Example: a person weighing 160 lb at 68 inches tall → (160 ÷ (68 × 68)) × 703 ≈ 24.4.

The resulting number is then placed into a category:

The BMI formula and the standard adult BMI categories are generally the same for men and women, so a women’s BMI calculator runs exactly the same maths as this one — although people with the same BMI can have different body compositions.

When you’d use this

Before having a detailed conversation with a doctor about weight and health; When you track your own weight trend over time, in a consistent and comparable unit; When you check a healthy weight range for a particular height (useful for fitness or nutrition planning discussions); When you enter a medical form or questionnaire, insurance form, fitness app, requiring BMI directly.

Dos and Don’ts

Do

1. Use BMI as a general screening tool.
2. Use the same unit system for both weight and height.
3. Discuss your result with a healthcare professional if you have concerns.

Don’t

1. Treat BMI as a complete assessment of your health.
2. Rely on BMI alone if you are very muscular or an athlete.
3. Use BMI during pregnancy as the main indicator of healthy weight.
4. Treat a BMI category as a medical diagnosis.

Good to know

BMI is a convenient and standardized indicator of an individual’s weight and height relationship, but has significant limitations. Does not differentiate between muscle and fat, and individuals with a higher degree of muscle may have a higher BMI even if they do not have surplus body fat.

BMI also does not reveal the location of body fat and doesn’t control for age-related variations in body composition. BMI should therefore be considered as a screening tool and not as a full health assessment, for the above reasons.

If you’re worried about your BMI, talk to your health care provider, who will take into account other factors including waist circumference, body composition, medical history, and lifestyle.

All calculations are performed client side in your browser, data entered is not uploaded to or stored on our servers.

Important: BMI is a screening tool and does not diagnose body fatness or overall health. Consult a healthcare professional for a full assessment.

FAQ: BMI Calculator Questions

FAQ: BMI Calculator Questions