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Reverse BMI: what weight gives it?

Type your height and the BMI you want. The reverse BMI calculator works the formula backwards and shows the weight that gives that BMI, the CDC healthy weight range at your height, and how far your current weight is from the target.

Your numbers

Units
Weight at this BMI
149 lb

At 5 ft 9 in, a BMI of 22 is a weight of 149 lb.

BMI category
Healthy weight
Healthy weight from
125.3 lb
Healthy weight below
169.3 lb

Weight at this BMI: 149 lb. At 5 ft 9 in, a BMI of 22 is a weight of 149 lb.

This calculator gives general information only. It is not medical advice and does not replace a doctor or other health care provider. Talk with a professional about your results. Terms of use

How to calculate

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.

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.

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

  • 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.

Machine-readable copies: Markdown, JSON.

Worked examples

Each example is checked against the calculator on every build.

  1. Height 5 ft 8.9 in, Target BMI 22 gives Weight at this BMI 148.5 lb, BMI category Healthy weight, Healthy weight from 124.9 lb, Healthy weight below 168.8 lb.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 5 ft 9 in, Target BMI 25, Current weight 180 lb gives Weight at this BMI 169.3 lb, BMI category Overweight, Change to reach it -10.7 lb.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 5 ft 4 in, Target BMI 18.5, Current weight 100 lb gives Weight at this BMI 107.8 lb, BMI category Healthy weight, Current BMI 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)

How it works

BMI is weight in kilograms divided by height in metres squared. Reversed:

  • Weight at this BMI = target BMI × height², in kilograms with height in metres. In US units this is the same as BMI × height (in)² ÷ 703, because 703 is about 0.45359237 ÷ 0.0254² (the page uses the exact metric form, so it does not round 703).
  • BMI category of the target BMI (CDC, adults): below 18.5 underweight; 18.5 to below 25 healthy weight; 25 to below 30 overweight; 30 or more obesity. The typed BMI is compared exactly (25 is overweight).
  • Healthy weight from = 18.5 × height². Healthy weight below = 25 × height²: the healthy range ends just below this weight.
  • Change to reach it (only when a current weight is typed) = target weight − current weight. Positive means a gain, negative a loss.
  • Current BMI (only with a current weight) = current weight ÷ height².

Rules. Height from 50 cm to 275 cm; target BMI from 10 to 80; current weight from 10 kg to 500 kg.

Exact arithmetic. Each typed value is read as the exact decimal you typed, in the unit you typed it in (5 ft 9 in is exactly 69 in = 1.7526 m; 180 lb is exactly 81.6466266 kg). Every result is worked out exactly from those decimals and rounded once.

Output format. Weights show 1 decimal in the unit of the page’s unit system (pounds in US, kilograms in Metric), rounded half up from the exact value. BMI shows 1 decimal, rounded half up. Trailing zeros are dropped. 1 lb = 0.45359237 kg and 1 in = 0.0254 m exactly.

Assumptions

  • Adults aged 20 and older.
  • BMI is a screening measure, not a diagnosis.

Worked examples by hand

175 cm, target BMI 22. 1.75² = 3.0625. Weight = 22 × 3.0625 = 67.375 kg (shown 67.4 kg). BMI 22 is a healthy weight. Healthy range: 18.5 × 3.0625 = 56.65625 kg to just below 25 × 3.0625 = 76.5625 kg.

5 ft 9 in, 180 lb now, target BMI 25. 69 in = 1.7526 m; 1.7526² = 3.07160676. Weight = 25 × 3.07160676 = 76.790169 kg = 169.29 lb (shown 169.3 lb; the CDC form 25 × 69² ÷ 703 = 169.31 agrees). 180 lb = 81.6466266 kg. Change = 76.790169 − 81.6466266 = −4.8564576 kg = −10.7 lb (a loss). BMI 25 is overweight.

5 ft 4 in, 100 lb now, target BMI 18.5. 64 in = 1.6256 m; 1.6256² = 2.64257536. Weight = 18.5 × 2.64257536 = 48.88764416 kg = 107.8 lb. Current BMI = 45.359237 ÷ 2.64257536 = 17.16 (shown 17.2). BMI 18.5 is a healthy weight (18.5 counts as healthy).

Other questions people ask

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.