---
title: "BMI Calculator | Adult Body Mass Index & Weight Range | BQ Calculator"
canonical: "https://calculator.bqtools.com/bmi-calculator/"
description: "Calculate adult BMI in metric or US units, see the BMI category and estimate the weight interval corresponding to BMI 18.5–24.9 for your height."
---

# BMI Calculator

Calculate adult body mass index from height and weight, with clear category ranges and an estimated BMI 18.5–24.9 weight interval.

BQ Calculator · https://calculator.bqtools.com/bmi-calculator/

## Inputs

Share links contain only the values needed to recreate this calculation.

## BMI estimate

## BMI formula

```text
BMI = weightKg / heightMeters²
```

The calculator converts US measurements to kilograms and meters before applying the same formula. Intermediate values are not rounded before the final BMI is displayed.

## Adult category ranges

The page uses standard adult screening cut points: below 18.5, 18.5–24.9, 25.0–29.9 and 30 or above. The text label is intentionally descriptive rather than diagnostic.

## Healthy-weight range estimate

For the entered height, the calculator rearranges the BMI formula at 18.5 and 24.9 to show the corresponding weight interval. That interval is a mathematical BMI range, not a personalized ideal-weight prescription.

## Limitations

BMI does not distinguish muscle, bone and body fat, and it does not represent fat distribution, metabolic health, pregnancy or age-specific needs. This calculator is for adult informational use only.

## Frequently asked questions

### What is BMI?

Body mass index is weight in kilograms divided by height in meters squared. It is a screening measure, not a direct measurement of body fat or health.

### What BMI range does this calculator call healthy weight?

For adults, this page displays the commonly used 18.5 through 24.9 BMI interval as the healthy-weight range. Individual health assessment can require much more context.

### Is BMI accurate for athletes?

BMI can classify some muscular people at a higher category because it does not distinguish muscle from body fat. It can also miss other aspects of body composition.

### Can children use this BMI calculator?

No. This page is designed for adults. BMI interpretation for children and adolescents depends on age- and sex-specific growth charts rather than the adult categories shown here.

### Does a BMI category diagnose a condition?

No. BMI is a screening metric. A category alone does not diagnose a disease, determine fitness, or replace evaluation by a qualified health professional.

### Related calculators

All calculation inputs stay local to this browser.

## Machine-readable resources

- Calculator registry: https://calculator.bqtools.com/calculators.json
- Site index: https://calculator.bqtools.com/llms.txt
- Full agent text: https://calculator.bqtools.com/llms-full.txt
- Agent discovery index: https://calculator.bqtools.com/agent-index.json