Free Ideal Body Weight Calculator

Find Your Healthy Weight Range

See your ideal body weight using four established medical formulas — just enter your height and gender, no scale measurements required.

4 Medical Formulas
No Sign-Up Needed
Instant Results
Male & Female Formulas
4Formulas Averaged
< 30sTo Get Results
60+Years of Clinical Use
Ideal Body Weight Calculator
Devine, Robinson, Miller & Hamwi Formulas
Gender
Current weight is optional — it's only used to show how far you are from the healthy range.

Your Results

Ideal Weight (Avg)
Healthy Range
Diff. from Current
Fill in your height and gender, then press calculate.
Note: These formulas are decades-old reference equations originally built for medical dosing, not a diagnosis. Individual healthy weight varies with frame, muscle mass, and overall health — consult a professional for personalized guidance.
How It Works

Two Numbers, One Healthy Range

No scale, no tape measure — just your height and gender are enough to estimate a healthy weight range.

01

Enter Height & Gender

Choose your unit system, select male or female, and enter your height. Adding your current weight is optional.

02

We Run 4 Formulas

Your height is plugged into the Devine, Robinson, Miller, and Hamwi equations — four formulas developed over different decades.

03

Get Your Range

See your average ideal weight, the full healthy range across all four formulas, and how far your current weight is from it.

The Basics

What Is Ideal Body Weight?

Ideal body weight (IBW) is a height-and-gender-based estimate of a healthy weight, calculated from medical formulas that were originally developed in the 1960s–80s to help clinicians dose medications accurately — many drugs need to be dosed relative to lean body size rather than total weight.

Over time, these same formulas were adopted more broadly as a quick reference point for a "healthy" weight target. They're simple, fast, and require no equipment beyond a height measurement, which is why they remain popular today even outside clinical settings.

Why It Matters

Why People Still Use These Formulas

1

A Fast, Equipment-Free Estimate

All four formulas need only height and gender, making this one of the quickest ways to get a ballpark healthy-weight figure.

2

A Useful Starting Reference

IBW gives you a reasonable range to aim toward when setting a weight goal, especially if you have no other benchmark to start from.

3

Still Used in Clinical Settings

Hospitals and pharmacists still reference these exact formulas today for dosing certain medications and nutrition planning.

Importantly, ideal body weight is a reference point, not a strict target. It doesn't account for muscle mass, frame size, or individual body composition — a muscular athlete will often weigh well above their "ideal" weight while being perfectly healthy.

The Formula

How Ideal Body Weight Is Calculated

Each formula estimates weight in kilograms from height in inches, with a different starting point and rate of increase per inch above 5 feet (60 inches).

1974

Devine Formula

Men: 50.0 kg + 2.3 kg × (height in inches − 60)
Women: 45.5 kg + 2.3 kg × (height in inches − 60)

Most widely used in medicine today
1983

Robinson Formula

Men: 52 kg + 1.9 kg × (height in inches − 60)
Women: 49 kg + 1.7 kg × (height in inches − 60)

A refinement of the Devine formula

All Four Formulas

We calculate all four and average them for a more balanced estimate.

Swipe to see all columns →

FormulaYearMenWomen
Devine197450.0 kg + 2.3 kg × (in − 60)45.5 kg + 2.3 kg × (in − 60)
Robinson198352 kg + 1.9 kg × (in − 60)49 kg + 1.7 kg × (in − 60)
Miller198356.2 kg + 1.41 kg × (in − 60)53.1 kg + 1.36 kg × (in − 60)
Hamwi196448.0 kg + 2.7 kg × (in − 60)45.5 kg + 2.2 kg × (in − 60)

For heights under 5 feet, the "(height − 60)" term becomes negative, which simply lowers the result proportionally — the math still works correctly for shorter heights.

Reference Ranges

Healthy Weight Ranges by Height

These example ranges show the spread between the lowest and highest of the four formulas at common heights.

HeightMen (lbs)Women (lbs)
5'0"106–124100–117
5'4"130–136120–129
5'8"148–153138–141
6'0"161–177153–161
6'4"174–201165–181

What Affects Your Ideal Weight

iFrame size — larger bone structure shifts a healthy weight higher
iMuscle mass — athletes often weigh more than "ideal" while staying lean
iAge — body composition and bone density shift naturally over time
iBone density — denser bones add weight without added fat
iPregnancy or medical conditions — these formulas don't apply during pregnancy or certain illnesses

Figures above are illustrative averages across the four formulas and rounded for readability — use the calculator above for your exact numbers.

In Context

Ideal Weight vs Other Metrics

Ideal body weight is one of several tools for thinking about healthy weight — each measures something slightly different.

vs BMI

BMI uses height and weight together to classify a category (underweight, normal, overweight, obese)
IBW instead works backward from height alone to suggest a target weight range
Both ignore body composition, so a muscular person can score "high" on either despite low body fat
Try our BMI Calculator to see your category alongside your ideal weight range
%

vs Body Fat %

IBW formulas are decades old and were never designed to account for fat vs muscle
Body fat percentage measures what your weight is actually made of, which is far more precise
Two people at the same "ideal" weight can have very different body compositions and health profiles
Use our Body Fat Calculator for a more direct composition estimate
Taking Action

8 Steps Toward a Healthy Weight

Whether you're aiming to gain or lose, sustainable progress comes from a handful of consistent habits.

1

Adjust Calories Gradually

A moderate 300–500 calorie deficit (to lose) or surplus (to gain) per day produces steady, sustainable change.

2

Strength Train Regularly

Resistance training helps build or preserve muscle, which matters more for health than the number on the scale.

3

Prioritize Protein Intake

Around 0.7–1g of protein per pound of bodyweight supports muscle maintenance whether you're losing or gaining.

4

Sleep 7–9 Hours

Poor sleep disrupts hunger hormones and recovery, making weight changes in either direction harder to manage.

5

Stay Consistent

Small, repeatable habits — regular meals, regular training — beat extreme short-term measures over time.

6

Track Trends, Not Daily Fluctuations

Body weight swings day to day from water and food. Look at weekly averages instead of single readings.

7

Get Professional Guidance

A doctor, dietitian, or trainer can personalize a target that accounts for your frame, muscle mass, and health history.

+

Be Patient

Healthy weight change is typically 0.5–1% of bodyweight per week — gradual progress that's far more likely to last.

FAQ

Common Questions

Everything you need to know about ideal body weight and how it's calculated.

They're reasonable population-level estimates, not precise individual measurements. Because they only use height and gender, they can't account for muscle mass, frame size, or body composition — treat the result as a reference range, not an exact target.
Devine, Robinson, Miller, and Hamwi were each developed independently, in different decades, using different reference populations. They agree roughly but not exactly, which is why averaging them and looking at the full range is more useful than relying on just one.
The formulas themselves don't account for muscle mass at all — they only use height and gender. In practice, a muscular person will often weigh more than their calculated "ideal" weight while still being lean and healthy.
Athletes, especially those with significant muscle mass, are likely to fall above the calculated range. For that population, body fat percentage is a far more meaningful metric than ideal body weight.
60 inches equals 5 feet, which the original researchers used as a baseline height. Each formula starts with a base weight at 5 feet and adds a fixed amount for every inch taller (or subtracts for every inch shorter) than that.
That's common and not necessarily a cause for concern on its own. These formulas are a rough reference, not a clinical assessment — talk to a healthcare provider about what's healthy for your specific body and history.
No. These formulas were developed for general adult dosing reference and don't apply during pregnancy or with many medical conditions. Always follow guidance from your doctor in those situations.