BMI Prime is your BMI divided by 25 (the upper limit of normal BMI). A BMI Prime of 1.0 means you are exactly at the upper edge of normal. Below 1.0 is healthy or underweight; above 1.0 means overweight or obese. It makes it easy to see how far you are from the normal range.

How much should I weigh for my height?

This calculator shows the healthy weight range (BMI 18.5–24.9) for your exact height, plus ideal body weight estimates from four clinical formulas: Devine, Robinson, Miller, and Hamwi. These formulas differ slightly for men and women and can give you a more personalised target.

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BMI Calculator

Calculate your Body Mass Index with healthy weight range, body fat estimate, ideal weight (4 formulas), BMI Prime, and Ponderal Index. Supports US imperial and metric units.

📏 Your measurements

Sex

Age 25 yrs

Height 5 ft 10 in

Weight 165 lbs

lbs

Your BMI

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Enter your details and click Calculate

BMI scale

Underweight Normal Overweight Obese

1018.52530354050

BMI Prime

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BMI ÷ 25 (1.0 = upper normal)

Ponderal Index

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kg/m³ (normal: 11–15)

Body fat % (est.)

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Deurenberg formula

Fat mass (est.)

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Based on body weight

Lean mass (est.)

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Weight − fat mass

Weight status

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WHO classification

⚖️ Healthy weight range for your height

—Healthy range (BMI 18.5–24.9)—

You are —

🎯 Ideal body weight estimates

Devine formula

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Robinson formula

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Miller formula

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Hamwi formula

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📋 BMI classification (WHO)

Category	BMI range	Health risk
Underweight	< 18.5	Malnutrition risk
Normal weight	18.5 – 24.9	Low
Overweight	25.0 – 29.9	Enhanced
Obese Class I	30.0 – 34.9	Medium
Obese Class II	35.0 – 39.9	High
Obese Class III	≥ 40.0	Very high

📈 BMI history

Your BMI results will be saved here across sessions.

How we compare

Government tools like NIH/CDC are authoritative but minimal. We match calculator.net's depth while adding ideal weight formulas and BMI history tracking.

Feature	SEOTriggers	calculator.net	NIH / CDC	Harvard Health
BMI + category	✓	✓	✓	✓
Visual BMI gauge	✓	✓	✗	✗
Body fat % estimate	✓	✓	✗	✗
Ideal weight (4 formulas)	✓ 4 formulas	✓	✗	✗
BMI Prime + Ponderal Index	✓	✓	✗	✗
Healthy weight range for height	✓	✓	✓	✗
BMI history tracker	✓	✗	✗	✗
Ad-free	✓	✗ Ads	✓ Gov	✗

Features

📊

BMI gauge

Visual needle on a color-coded scale — instantly see where you sit between underweight and obese.

🎯

Ideal weight — 4 formulas

Devine, Robinson, Miller, and Hamwi formulas each give a slightly different target weight for your height and sex.

💪

Body fat estimate

Deurenberg formula estimates body fat percentage from BMI, age, and sex — more useful than BMI alone.

📈

BMI history

Every result is saved in your browser. Check back monthly to track your progress over time.

🔢

BMI Prime & Ponderal

BMI Prime shows how far you are from the normal limit (1.0). Ponderal Index accounts for height scaling.

🔄

Imperial & metric

Switch between lbs/ft/in and kg/cm with one click — inputs convert automatically.

FAQ

What is a healthy BMI for adults?

For adults 20 and older, a BMI between 18.5 and 24.9 is considered healthy weight by WHO. Below 18.5 is underweight, 25–29.9 is overweight, and 30 or above is classified as obese (Class I, II, or III depending on severity).

Is BMI accurate for women and men differently?

BMI uses the same scale for both sexes but women naturally carry more fat than men at the same BMI. This calculator provides a sex-adjusted body fat estimate using the Deurenberg formula (Body fat % = 1.2 × BMI + 0.23 × Age − 10.8 × Sex − 5.4, where Sex = 1 for male, 0 for female), which gives a more meaningful picture.

What is BMI Prime?

BMI Prime is your BMI divided by 25 — the upper limit of the normal range. A value of exactly 1.0 means you are right at the edge of normal weight. Below 1.0 is healthy or underweight; above 1.0 means overweight or obese. It lets you instantly see how far from the normal limit you are, in relative terms.

How is ideal body weight calculated?

Four clinical formulas are shown: Devine (most widely used clinically), Robinson, Miller, and Hamwi. Each uses height in inches and adjusts for sex. They differ slightly — Hamwi tends to give higher values for tall individuals, while Miller gives slightly lower ones. Using all four gives a realistic target range rather than a single number.

⚠️ Medical disclaimer: This calculator provides general health information only. BMI has limitations — it does not account for muscle mass, bone density, or fat distribution. Consult a licensed healthcare provider before making any health or dietary decisions.