# Reverse BMI: what weight gives it?

Works BMI backwards: the body weight that gives a chosen BMI at your height (BMI × height²), the healthy weight range for that height, and how far a current weight is from it.

- Page: https://www.acalculator.org/health/reverse-bmi-calculator
- JSON spec: https://www.acalculator.org/health/reverse-bmi-calculator.json
- Version: 6af94e473c6a

## Default answer

Example with the default inputs (Height 5 ft 9 in, Target BMI 22): At 5 ft 9 in, a BMI of 22 is a weight of 149 lb.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| height | Height | Your height without shoes. |
| bmi | Target BMI | The body mass index you want the weight for; 18.5 to below 25 is the CDC healthy range. |
| now | Current weight | Optional: your weight now, to see how much it is from the target. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| weight | Weight at this BMI | Target BMI × height², in kilograms or pounds. |
| category | BMI category | The CDC adult category of the target BMI. |
| healthyMin | Healthy weight from | BMI 18.5 × height²: the lowest weight in the CDC healthy range. |
| healthyMax | Healthy weight below | BMI 25 × height²: the healthy range ends just below this weight. |
| change | Change to reach it | Target weight − current weight: positive is a gain, negative a loss. |
| currentBmi | Current BMI | Current weight ÷ height². |

## Method

Weight = BMI × height² (kg and m); in US units, weight (lb) = BMI × height (in)² ÷ 703.

## Assumptions

- Adults aged 20 and older; children and teens use BMI-for-age percentiles instead.
- The CDC adult categories: underweight below 18.5, healthy 18.5 to below 25, overweight 25 to below 30, obesity 30 or more.
- BMI is a screening measure; it does not measure body fat directly.

## Worked examples

1. height = 1.75, bmi = 22 gives weight = 67.375, category = Healthy weight, healthyMin = 56.65625, healthyMax = 76.5625. Source: CDC, Adult BMI Categories: BMI = weight (kg) ÷ height (m)²; underweight below 18.5, healthy weight 18.5 to below 25, overweight 25 to below 30, obesity 30 or more, https://www.cdc.gov/bmi/adult-calculator/bmi-categories.html (retrieved 2026-10-05).
2. height = 1.7526, bmi = 25, now = 81.646627 gives weight = 76.790169, category = Overweight, change = -4.856458. Source: CDC, Adult BMI Categories: BMI = weight (kg) ÷ height (m)²; underweight below 18.5, healthy weight 18.5 to below 25, overweight 25 to below 30, obesity 30 or more, https://www.cdc.gov/bmi/adult-calculator/bmi-categories.html (retrieved 2026-10-05); 25 × 69² ÷ 703 = 169.3 lb (CDC English formula), so 10.7 lb to lose.
3. height = 1.6256, bmi = 18.5, now = 45.359237 gives weight = 48.887644, category = Healthy weight, currentBmi = 17.164785. Source: CDC, Adult BMI Categories: BMI = weight (kg) ÷ height (m)²; underweight below 18.5, healthy weight 18.5 to below 25, overweight 25 to below 30, obesity 30 or more, https://www.cdc.gov/bmi/adult-calculator/bmi-categories.html (retrieved 2026-10-05).

## FAQ

### How do I calculate weight from BMI?

Multiply the BMI by your height squared. In metric units, weight (kg) = BMI × height (m)²: a BMI of 22 at 1.75 m is 22 × 3.0625 = 67.4 kg. In US units, weight (lb) = BMI × height (in)² ÷ 703.

### What weight is a BMI of 25 at 5 ft 9 in?

25 × 69² ÷ 703 = 169.3 lb (76.8 kg). That is where the CDC overweight category starts, so the healthy range at 5 ft 9 in ends just below it.

### What is a healthy BMI for adults?

The CDC calls a BMI from 18.5 to below 25 a healthy weight for adults aged 20 and older. Below 18.5 is underweight, 25 to below 30 overweight, and 30 or more obesity.

### Why is a reverse BMI useful?

It turns a BMI goal into a weight you can track on a scale. Setting a target BMI of 24, for example, gives the weight to aim for at your height, and the page shows how much that is to gain or lose.

### Does a reverse BMI work for children?

No. Children and teens are compared with others of the same age and sex using BMI-for-age percentiles, so a single BMI target does not apply to them.

### Is BMI a good measure of body fat?

BMI is a quick screening number. It does not tell muscle from fat, so very muscular people can have a high BMI without extra fat. A waist measurement or a clinician’s check adds detail.

## Sources

- Centers for Disease Control and Prevention. Adult BMI Categories, retrieved 2026-10-05. https://www.cdc.gov/bmi/adult-calculator/bmi-categories.html
- Centers for Disease Control and Prevention. Body Mass Index (BMI): the formula, kg/m² and 703 × lb/in², retrieved 2026-10-05. https://www.cdc.gov/bmi/faq/index.html
- NIST Special Publication 811, Appendix B: 1 lb = 0.45359237 kg and 1 in = 2.54 cm exactly, retrieved 2026-10-05. https://www.nist.gov/pml/special-publication-811