BMI Calculator

Calculate your Body Mass Index instantly in metric or imperial units. See your BMI category, healthy weight range, and where you fall on the BMI scale — all in your browser, no data sent anywhere.

cm
50 cm250 cm
kg
10 kg200 kg
yr

Age and gender are included in your copy summary for reference only.

BMI Result

Body Mass Index

24.2

Normal weight

BMI range: 18.5 – 24.9

BMI Scale

1018.5253040+
Underweight
Normal weight
Overweight
Obese
Healthy Weight Range
53.5 – 72
kg for your height · BMI 18.5 – 24.9
Status
Within range ✓
You are in the healthy range

A BMI in this range is generally associated with good health.

BMI is a screening tool, not a diagnostic measure. It does not account for muscle mass, bone density, age, or sex. Consult a healthcare professional for a complete health assessment.

About this tool

A straightforward BMI calculator that works in both metric (cm / kg) and imperial (ft·in / lbs) units. Switch between unit systems at any time — your inputs are automatically converted so you never have to re-enter values. Sliders, presets, and direct number inputs let you explore different height and weight combinations quickly.

The result panel shows your numeric BMI, the corresponding WHO category, a colour-coded scale indicating where your BMI sits relative to all categories, and the healthy weight range for your height. BMI is an informational reference value — it is not a medical diagnosis. Always consult a qualified healthcare professional for personal health guidance.

How to use

1

Choose your unit system

Toggle between Metric (centimetres and kilograms) and Imperial (feet, inches, and pounds) using the unit switch at the top of the input panel. Your values convert automatically.

2

Enter height and weight

Drag the sliders or type directly into the number fields. Use the quick preset chips — common heights and weights — to jump to a value without typing.

3

Read your BMI

Your BMI appears instantly in the result panel along with the category (Underweight, Normal, Overweight, or Obese) and a colour-coded scale showing where your value sits.

4

Check your healthy weight range

The stat cards show the healthy weight range for your height (BMI 18.5–24.9) and how much weight you would need to gain or lose to reach it — or a checkmark if you are already within it.

Related tools

Age Calculator

Calculate your exact age in years, months, and days from your date of birth.

Unit Converter

Convert between metric and imperial units for length, weight, temperature, and more.

Percentage Calculator

Calculate percentage of a number, percentage change, or what percentage one number is of another.

Discount Calculator

Find the final price after applying a percentage discount to any amount.

Frequently asked questions

Common questions about BMI, how it is calculated, and what the categories mean.

Body Mass Index (BMI) is a number calculated from your height and weight. It is used as a general screening tool to indicate whether a person has a body weight that may be appropriate for their height. BMI does not directly measure body fat, muscle mass, or body composition — it is a rough population-level indicator, not a diagnostic tool.

In metric units: BMI = weight (kg) ÷ height² (m²). In imperial units: BMI = 703 × weight (lbs) ÷ height² (inches²). For example, a person who is 170 cm tall and weighs 70 kg has a BMI of 70 ÷ (1.70 × 1.70) = 24.2.

The standard BMI categories for adults (18+) are: Underweight (below 18.5), Normal weight (18.5–24.9), Overweight (25–29.9), and Obese (30 and above). These categories are defined by the World Health Organization (WHO) and are used as reference ranges, not clinical diagnoses.

BMI has well-known limitations. It does not account for muscle mass, bone density, fat distribution, age, sex, or ethnicity. Athletes with high muscle mass may be classified as overweight despite having low body fat. Older adults may have a 'normal' BMI but carry excess body fat. BMI is best used as one data point among several, not as a standalone health measure.

No. For children and teenagers (ages 2–19), BMI is interpreted differently using age- and sex-specific percentile charts rather than fixed cutoffs. This calculator uses the standard adult BMI categories and is intended for adults aged 18 and above. For children, consult a pediatric healthcare provider.

The healthy weight range is the range of body weights that correspond to a BMI between 18.5 and 24.9 for your specific height. It gives a practical reference — not a target or prescription. Individual healthy weight can vary based on muscle mass, bone structure, and other factors not captured by BMI.

No. All calculations happen entirely in your browser using JavaScript. Your height, weight, age, and gender inputs are never sent to any server and are not stored beyond your current browser session.