What is Ideal Body Weight (IBW)?

IBW is a clinical estimate of healthy body weight based on height and sex, historically used in medicine to calculate drug dosages.

Which ideal weight formula is the best?

The Devine formula is the most widely used medical standard, which is why this calculator uses it. Robinson, Miller, and Hamwi are close alternatives that shift the estimate by only a few pounds.

How does height affect ideal weight?

Formulas use 5 feet (60 inches) as a baseline, adding a set amount of weight (usually 1.4 to 2.7 kg) for each inch above that limit.

Why do formulas differ by sex?

Biologically, men have higher muscle mass and bone density, while women have higher essential body fat percentages, requiring separate calculations.

Does this calculator apply to bodybuilders?

No. The formulas do not account for muscle mass. Highly muscular individuals will exceed their predicted ideal weight but still be healthy.

What is the Devine formula?

Men: 50.0 kg + 2.3 kg per inch over 5 feet. Women: 45.5 kg + 2.3 kg per inch over 5 feet.

What is the Hamwi formula?

Men: 48.0 kg + 2.7 kg per inch over 5 feet. Women: 45.5 kg + 2.2 kg per inch over 5 feet.

What is the healthy BMI-based weight range?

A weight range that keeps your BMI between 18.5 and 24.9, which is often broader and more realistic than single-point formulas.

How do I determine my body frame size?

Frame size can be estimated by measuring wrist circumference relative to height. This calculator does not apply a frame-size adjustment directly, but a small or large frame is a reasonable justification for leaning toward the low or high end of the healthy BMI-range weight it displays.

health calculator

Ideal Weight Calculator

Find your ideal weight range based on height, gender, and body frame using trusted medical formulas for a healthy target.

Formula Verified by Dr. Sarah Jenkins, PhD

Quick actions: Save inputs, view saved runs, print, share, or export results

Saved Runs

Inputs

Mode

Sex

Current Weight (optional)lb

Height (feet)

Height (inches)

Results

Devine (most validated)

59.3 kg (130.7 lb)

Robinson59.2 kg (130.5 lb)

Miller61.3 kg (135.1 lb)

Hamwi58.7 kg (129.4 lb)

Broca67.6 kg (149.1 lb)

Lorentz58.8 kg (129.7 lb)

Healthy BMI Range52.0 kg–70.0 kg

Your Weight150.0 lb — within the healthy BMI range

Tip

Save this page to compare formulas, track progress toward a target BMI, or check weight guidelines by frame size.

Formula

Ideal weight formulas

Devine: Men 50.0 kg + 2.3 kg/inch over 5 ft, Women 45.5 kg + 2.3 kg/inch over 5 ft. Healthy BMI range: 18.5-24.9 × height(m)^2. Target weight: Target BMI × height(m)^2.

Six classical formulas are computed together, alongside the BMI-based healthy range and a target-BMI solver.

Step by step

How the calculation works

1Choose Compare Formulas, Target BMI, or Weight by Frame Size mode.
2Compare Formulas: enter sex, height, and optional current weight to see all six ideal-weight formulas plus the healthy BMI range.
3Target BMI: enter height, current weight, and a target BMI to see the exact weight needed and the gap from your current weight.
4Weight by Frame Size: enter sex, height, and frame size to see the traditional weight-by-frame guideline for your build.

Related guides

Learn more about this calculation

Guide

Ideal Weight Range: Height-Based Estimates and Their Limits

Understand ideal weight formulas, healthy BMI ranges, and why a useful weight target is usually a range, not one perfect number.

Guide

BMI Calculation Guide: Formula, Ranges, and Limits

Calculate adult BMI by hand, understand the standard ranges, and learn why BMI is a screening measure rather than a diagnosis.

BMI

BMI Calculator

Calculate your Body Mass Index and see your healthy weight range directly.

Body Composition

Body Fat Calculator

Estimate body fat percentage from waist, neck, and height measurements.

Metabolism

BMR Calculator

Estimate your basal metabolic rate and daily calorie needs at rest.

Calories

Calorie Calculator

Estimate daily calorie needs for weight loss, maintenance, or muscle gain.

Nutrition

Protein Calculator

Estimate your ideal daily protein intake based on body weight and goals.

Macros

Macro Calculator

Calculate daily protein, carb, and fat targets based on your calorie needs.

How to understand and use this calculator

Quick Answer

What is ideal body weight? Ideal body weight (IBW) is an estimate of what a healthy person should weigh based on height and sex. Doctors, nutritionists, and fitness professionals use it as a general guideline — not a strict target.

The most validated formula (Devine):

Men: 50.0 kg + 2.3 kg for each inch over 5 feet
Women: 45.5 kg + 2.3 kg for each inch over 5 feet

Quick examples (Devine formula):

5'6" female: ideal weight ≈ 59.3 kg (130.7 lb)
5'10" male: ideal weight ≈ 73.0 kg (160.9 lb)
5'5" female: ideal weight ≈ 57.0 kg (125.7 lb)

Healthy BMI range: 18.5–24.9 — remember this is a weight range, not a single number.

How much are you supposed to weigh? It depends on your height, sex, and body composition. Use the calculator above to get your personalized range from all six formulas at once.

Use the Ideal Weight Calculator

This calculator has three modes, matching the three things people actually need from an ideal-weight tool:

Compare Formulas — enter your sex, height, and (optionally) your current weight to see all six ideal-weight formulas plus your healthy BMI range at once.
Target BMI — enter your height and current weight, pick a target BMI, and see exactly how much you need to gain or lose to reach it.
Weight by Frame Size — enter your sex, height, and frame size (small, medium, or large) to see the traditional weight-by-frame guideline for your build.

Example input (Compare Formulas mode): Female, height 5'6" (66 in), current weight 150 lb.

Output: Devine = 59.3 kg (130.7 lb) • Robinson = 59.2 kg (130.5 lb) • Miller = 61.3 kg (135.1 lb) • Hamwi = 58.7 kg (129.4 lb) • Broca = 67.6 kg (149.1 lb) • Lorentz = 58.8 kg (129.7 lb) • Healthy BMI range = 52.0–70.0 kg (114.6–154.3 lb) • Current weight 150 lb (68.0 kg) sits above the healthy BMI range.

Example input (Target BMI mode): Female, height 5'6", current weight 150 lb, target BMI 21.7.

Output: Target weight = 61.0 kg (134.5 lb) • You would need to lose about 15.5 lb to reach a BMI of 21.7.

What Is Ideal Body Weight?

Ideal Body Weight (IBW) is an estimate of what a healthy person of your height and sex should weigh. It is not a strict number but a general clinical guideline.

Key points:

Ideal weight varies by height and sex.
It's an estimate, not a precise measurement.
It doesn't account for muscle mass or body composition.
It is useful for setting health and fitness goals, not for diagnosing anyone.

How much are you supposed to weigh depends on:

Your height — taller people generally weigh more.
Your sex — men typically carry more lean mass than women at the same height.
Your body composition — muscle is denser than fat, so it weighs more per unit of volume.
Your frame size — small, medium, and large frames shift the healthy range up or down.

Two people of the same height and sex can have very different healthy weights depending on their body composition — ideal weight is a starting point, not a rule.

Why Ideal Weight Matters

Maintaining a weight near your healthy range is linked to several measurable benefits: lower risk of heart disease, diabetes, and stroke; a more efficient metabolism; less strain on joints; better sleep quality; and lower long-term mortality risk.

Being underweight carries its own risks: weakened immunity, lower bone density, hormonal disruptions that can affect fertility, and persistent fatigue.

Being overweight carries related risks: higher blood pressure and cholesterol, a strong correlation with type 2 diabetes, added strain on joints, and a higher likelihood of sleep apnea.

This is why the calculator shows a range rather than one number — health outcomes track a band of healthy weights, not a single exact figure.

The Devine Formula — Most Validated Method

The Devine formula is the most medically validated ideal-weight formula, and the one doctors and pharmacists use for medication dosing (especially drugs that do not distribute into fat tissue, like many anesthetics and chemotherapy agents).

The formula:

Men: 50.0 kg + 2.3 kg per inch over 5 feet
Women: 45.5 kg + 2.3 kg per inch over 5 feet

Step-by-step example 1: 5'6" female

Step 1 — convert height to inches: 5'6" = 66 in.
Step 2 — inches over 5 feet: 66 − 60 = 6 in.
Step 3 — apply the formula: 45.5 + (2.3 × 6) = 45.5 + 13.8 = 59.3 kg (130.7 lb).

Step-by-step example 2: 5'10" male

Step 1 — convert height to inches: 5'10" = 70 in.
Step 2 — inches over 5 feet: 70 − 60 = 10 in.
Step 3 — apply the formula: 50.0 + (2.3 × 10) = 50.0 + 23.0 = 73.0 kg (160.9 lb).

Other Ideal Weight Formulas Compared

Besides Devine, four other formulas are commonly cited, all using the same "kg + kg per inch over 5 feet" structure except Broca and Lorentz, which work directly from height in centimeters:

Robinson (1983): Men 52.0 kg + 1.9 kg/inch over 5'; Women 49.0 kg + 1.7 kg/inch over 5'. A modification of Devine.
Miller (1983): Men 56.2 kg + 1.41 kg/inch over 5'; Women 53.1 kg + 1.36 kg/inch over 5'. Another Devine modification with a gentler slope.
Hamwi (1964): Men 48.0 kg + 2.7 kg/inch over 5'; Women 45.5 kg + 2.2 kg/inch over 5'. Common in clinical nutrition settings.
Broca: height (cm) − 100, for both sexes. Simple, but less accurate — it ignores sex entirely.
Lorentz: Men (height − 100) − (height − 150)/4; Women (height − 100) − (height − 150)/2. Popular in parts of Europe.

All six formulas for a 5'6" (167.6 cm) female:

Devine: 59.3 kg (130.7 lb)
Robinson: 59.2 kg (130.5 lb)
Miller: 61.3 kg (135.1 lb)
Hamwi: 58.7 kg (129.4 lb)
Broca: 67.6 kg (149.1 lb)
Lorentz: 58.8 kg (129.7 lb)

All six formulas for a 5'10" (177.8 cm) male:

Devine: 73.0 kg (160.9 lb)
Robinson: 71.0 kg (156.5 lb)
Miller: 70.3 kg (155.0 lb)
Hamwi: 75.0 kg (165.3 lb)
Broca: 77.8 kg (171.5 lb)
Lorentz: 70.9 kg (156.2 lb)

Notice the spread — even among validated formulas, ideal weight estimates for the same person can vary by 5–10 kg (10–20 lb). That spread is exactly why treating any single number as a strict target is a mistake; use the Compare Formulas mode above to see your own spread.

BMI and Ideal Weight — The Healthy Range

BMI (Body Mass Index) measures body weight relative to height. It is the basis for the "healthy range" shown alongside every formula result.

The formula: BMI = Weight (kg) ÷ Height (m)²

BMI categories:

Below 18.5 — Underweight
18.5–24.9 — Normal (healthy)
25.0–29.9 — Overweight
30.0 and above — Obese

Finding your healthy weight range from BMI:

Step 1 — convert height to meters.
Step 2 — minimum healthy weight = 18.5 × (height in meters)².
Step 3 — maximum healthy weight = 24.9 × (height in meters)².

Worked example: 5'6" female (167.64 cm = 1.6764 m)

Minimum: 18.5 × 1.6764² = 18.5 × 2.8103 = 52.0 kg (114.6 lb)
Maximum: 24.9 × 1.6764² = 24.9 × 2.8103 = 70.0 kg (154.3 lb)
Healthy range: 52.0–70.0 kg (114.6–154.3 lb)

Solving Backward: Finding the Weight to Hit a Target BMI

Most ideal-weight tools only go one direction: height in, weight out. The Target BMI mode solves the problem backward — you pick the BMI you want to reach, and the calculator tells you the exact weight (and how much to gain or lose from your current weight) to get there.

Formula: Target weight (kg) = Target BMI × Height (m)²

Worked example: height 5'6" (1.6764 m), target BMI 21.7 (a common "healthy midpoint" target).

Target weight = 21.7 × 1.6764² = 21.7 × 2.8103 = 61.0 kg (134.5 lb).
If your current weight is 150 lb (68.0 kg), you would need to lose 68.0 − 61.0 = 7.0 kg (≈15.5 lb) to reach BMI 21.7.

This is especially useful for setting a concrete, realistic goal weight instead of aiming vaguely at "somewhere in the healthy range." Pair it with the BMI Calculator to track your BMI as you go.

Weight Guidelines by Height, Sex, and Frame Size

Ideal-weight formulas assume an average frame. Traditional height-weight guidelines (originally built from life-insurance mortality data) instead give a weight range for small, medium, and large body frames at each height — which is exactly what the Weight by Frame Size mode calculates for any height, not just the handful of heights in an old printed chart.

How to estimate your frame size: measure your wrist circumference.

Small: wrist under 6.5" (women) or under 6.75" (men)
Medium: wrist 6.5"–7.5" (women) or 6.75"–7.5" (men)
Large: wrist over 7.5"

Reference points for women (medium frame):

5'0": 105–115 lb
5'4": 115–125 lb
5'6": 125–135 lb
5'8": 130–140 lb
5'10": 135–145 lb

Reference points for men (medium frame):

5'6": 135–145 lb
5'8": 140–150 lb
5'10": 145–155 lb
6'0": 150–160 lb
6'2": 155–165 lb

A large frame shifts the range higher; a small frame shifts it lower. These bands are a traditional reference, not a clinical formula — use them alongside, not instead of, the Devine and BMI-based figures above.

How to Calculate Ideal Weight in Excel

Every formula on this page is a one-line spreadsheet formula. Put height in inches in cell B1 and sex ("M" or "F") in cell B2.

Devine formula: =IF(B2="M", 50+2.3*MAX(B1-60,0), 45.5+2.3*MAX(B1-60,0)) — result in kg; multiply by 2.2046226218 to convert to lb.

Robinson formula: =IF(B2="M", 52+1.9*MAX(B1-60,0), 49+1.7*MAX(B1-60,0))

Miller formula: =IF(B2="M", 56.2+1.41*MAX(B1-60,0), 53.1+1.36*MAX(B1-60,0))

Hamwi formula: =IF(B2="M", 48+2.7*MAX(B1-60,0), 45.5+2.2*MAX(B1-60,0))

Broca formula (height in cm in B3): =B3-100

Lorentz formula (height in cm in B3): =IF(B2="M", (B3-100)-(B3-150)/4, (B3-100)-(B3-150)/2)

Healthy BMI weight range (height in meters in B4): Minimum =18.5*B4^2, Maximum =24.9*B4^2

Target weight for a goal BMI (target BMI in B5): =B5*B4^2

BMI itself (weight in kg in B6): =B6/B4^2 — or in imperial units, with height in inches in B1 and weight in lb in B6: =703*B6/B1^2

Real-World Ideal Weight Examples

Example 1 — 5'2" female, small frame: Devine ≈ 50.1 kg (110.5 lb). Weight-by-frame guideline (small): roughly 105–115 lb, comparable to the Devine estimate.

Example 2 — 6'2" male, comparing formulas: Devine = 82.2 kg (181.2 lb); Robinson = 78.6 kg (173.3 lb); Hamwi = 85.8 kg (189.2 lb). The spread across formulas is about 7 kg (16 lb) — a reminder to treat any single number as an estimate.

Example 3 — 5'9" male at 200 lb wanting BMI 24: target weight = 24 × (1.7526 m)² = 24 × 3.0716 = 73.7 kg (162.5 lb). He would need to lose about 37.5 lb to reach BMI 24.

Example 4 — 5'4" female, large frame: weight-by-frame guideline (large): roughly 120–130 lb, close to the Devine medium-frame-style estimate of 54.7 kg (120.6 lb) — for a genuinely large frame, aim toward the upper half of that band rather than at the Devine figure itself.

Practice Problems

Problem 1: What is the Devine ideal weight for a 5'6" female? Solution: height = 66 in, 6 in over 5 ft. 45.5 + (2.3 × 6) = 45.5 + 13.8 = 59.3 kg (130.7 lb).

Problem 2: What is the Devine ideal weight for a 5'10" male? Solution: height = 70 in, 10 in over 5 ft. 50.0 + (2.3 × 10) = 50.0 + 23.0 = 73.0 kg (160.9 lb).

Problem 3: What is the healthy BMI weight range for a 5'5" female (1.651 m)? Solution: Minimum = 18.5 × 1.651² = 18.5 × 2.7258 = 50.4 kg (111.2 lb). Maximum = 24.9 × 1.651² = 24.9 × 2.7258 = 67.9 kg (149.6 lb). Range: 50.4–67.9 kg (111.2–149.6 lb).

Problem 4: What is the Devine ideal weight for a 5'5" female? Solution: height = 65 in, 5 in over 5 ft. 45.5 + (2.3 × 5) = 45.5 + 11.5 = 57.0 kg (125.7 lb).

Problem 5: A 5'8" male weighs 190 lb and wants a BMI of 23. What weight should he target, and how much does he need to lose? Solution: height = 1.7272 m. Target weight = 23 × 1.7272² = 23 × 2.9832 = 68.6 kg (151.2 lb). He needs to lose 190 − 151.2 = 38.8 lb.

Answers: 1) 59.3 kg (130.7 lb) — 2) 73.0 kg (160.9 lb) — 3) 50.4–67.9 kg (111.2–149.6 lb) — 4) 57.0 kg (125.7 lb) — 5) target 151.2 lb, lose 38.8 lb.

Common Ideal Weight Mistakes

Treating ideal weight as a strict number. Mistake: believing you must weigh exactly the formula result. Fix: use it as a midpoint of a reasonable range, not a hard target.
Ignoring muscle mass. Mistake: not accounting for muscle, which is denser than fat. Fix: cross-check with the Body Fat Calculator before assuming you need to lose weight.
Using the wrong formula for your sex. Mistake: applying the male formula to a female height or vice versa. Fix: always confirm the sex-specific constant before calculating by hand.
Ignoring frame size. Mistake: using one number for every build. Fix: check the Weight by Frame Size mode above, especially if you have a notably small or large frame.
Focusing only on weight. Mistake: ignoring other health markers. Fix: consider blood pressure, cholesterol, and fitness level alongside weight — pair this tool with the BMI Calculator and BMR Calculator.
Applying adult formulas to children or teens. Mistake: these formulas assume a fully grown adult skeleton. Fix: use pediatric growth charts instead.
Confusing weight loss with fat loss. Mistake: chasing a lower number on the scale. Fix: focus on body composition — the Calorie Calculator can help set a realistic, sustainable deficit.
Skipping medical guidance. Mistake: making health decisions from a calculator alone. Fix: use these numbers as a conversation starter with a doctor or registered dietitian, not a replacement for one.

Ideal Weight vs. BMI vs. Body Fat vs. Frame Size

Ideal weight formulas (Devine, Robinson, Miller, Hamwi, Broca, Lorentz) give a single-point weight estimate from height and sex only.

BMI gives a healthy weight *range* from height alone, and is the basis for the range shown next to every formula on this page. Check it directly with the BMI Calculator.

Body fat percentage measures composition — how much of your weight is fat versus lean mass — which none of the weight-based formulas above can see. Two people at an identical "ideal weight" can have very different body fat percentages; the Body Fat Calculator fills that gap.

Frame size adjusts the expected weight up or down for skeletal build, independent of muscle or fat — see the Weight by Frame Size mode above.

Used together, these four tools give a far more complete picture than any single number: ideal weight as a starting estimate, BMI for a healthy range, body fat for composition, and frame size for build.

What This Calculator Can and Cannot Do

This calculator CAN help with:

Estimating ideal weight using six validated formulas at once
Finding your healthy BMI weight range
Solving backward for the weight needed to hit a target BMI
Checking the traditional weight-by-frame-size guideline for any height
Setting realistic health and fitness goals

This calculator CANNOT do:

Account for muscle mass or body composition directly
Provide personalized medical advice
Replace a doctor's assessment or diagnostic evaluation
Determine whether you specifically should gain or lose weight
Account for pregnancy or existing medical conditions
Apply to children or teenagers — these formulas assume a fully grown adult

Final Summary

An ideal weight calculator is a useful starting point for understanding what a healthy weight might look like for your height and sex — but it works best as a range, not a single target. Compare all six classical formulas, solve backward for a target BMI, and check the frame-size guideline before drawing conclusions.

Remember the key formulas:

Devine (men): 50.0 kg + 2.3 kg/inch over 5 feet
Devine (women): 45.5 kg + 2.3 kg/inch over 5 feet
Healthy BMI range: 18.5–24.9
Target weight for a goal BMI: Target BMI × Height (m)²

Quick reference:

5'6" female: ≈59.3 kg (130.7 lb) Devine, 52.0–70.0 kg (114.6–154.3 lb) healthy range
5'10" male: ≈73.0 kg (160.9 lb) Devine, 58.5–78.7 kg (128.9–173.5 lb) healthy range

Start now — enter your height and sex above to see your personalized range across all three modes, completely free.

Related concepts

Devine Formula

The most medically validated ideal-weight formula, used clinically for medication dosing calculations.

Body Mass Index (BMI)

A weight-to-height ratio that defines the healthy weight range shown alongside every ideal-weight formula.

Frame Size

A classification of skeletal build (small, medium, large) that shifts the expected healthy weight up or down.

Lean Body Mass

The weight of everything in your body except fat — muscle, bone, and water — which weight-only formulas cannot measure directly.

Frequently Asked Questions

What is an ideal weight calculator?+

An ideal weight calculator estimates what a healthy person of your height and sex should weigh, using validated clinical formulas such as Devine, Robinson, Miller, and Hamwi.

How much am I supposed to weigh?+

It depends on your height, sex, and body composition. Use the Compare Formulas mode above to see your personalized range across six formulas plus the healthy BMI range.

What is the average weight of a 5'5" female?+

According to the Devine formula, the ideal weight for a 5'5" female is about 57.0 kg (125.7 lb). The healthy BMI weight range for that height is approximately 50.4–67.9 kg (111.2–149.6 lb).

What is the ideal weight for a 5'6" female?+

According to the Devine formula, the ideal weight for a 5'6" female is about 59.3 kg (130.7 lb). The healthy BMI weight range is approximately 52.0–70.0 kg (114.6–154.3 lb).

What is the most accurate ideal weight formula?+

The Devine formula is the most widely used and medically validated, especially for medication dosing. Robinson, Miller, and Hamwi are close alternatives that shift the estimate by a few kilograms.

What is a healthy BMI range?+

A healthy BMI range is 18.5 to 24.9. Below 18.5 is considered underweight, 25.0–29.9 overweight, and 30.0 and above obese.

How do I calculate my ideal weight?+

Use the Devine formula: for men, 50.0 kg + 2.3 kg per inch over 5 feet; for women, 45.5 kg + 2.3 kg per inch over 5 feet. Or enter your height and sex into the calculator above to see all six formulas at once.

How much weight do I need to gain or lose to reach a healthy BMI?+

Switch to the Target BMI mode, enter your height, current weight, and target BMI, and the calculator shows the exact target weight and the gap from your current weight.

Can ideal weight calculators be wrong?+

They're estimates, not measurements. They don't account for muscle mass, frame size, or individual variation, so treat the result as a starting point, not a verdict.

Should I use ideal weight for weight loss goals?+

Use it as a general guideline alongside your healthy BMI range, but focus on overall health, body composition, and fitness rather than hitting one exact number.

What if I have a large or small frame?+

If you have a large frame, your realistic ideal weight likely sits toward the higher end of the healthy range; a small frame typically sits toward the lower end. Check the Weight by Frame Size mode above for a guideline specific to your height.

Is ideal weight the same as healthy weight?+

Not exactly. Ideal weight (from formulas like Devine) is a single-point estimate. Healthy weight is a range based on BMI (18.5–24.9) for your height — usually a wider and more realistic target.

Does ideal weight change with age, or apply during pregnancy or to children?+

These formulas assume a fully grown adult and do not adjust for age, and they do not apply during pregnancy or to children and teenagers, who should be assessed with pediatric growth charts instead.

Is this ideal weight calculator free?+

Yes — completely free, with no registration required.

How the calculation works

1Choose Compare Formulas, Target BMI, or Weight by Frame Size mode.

2Compare Formulas: enter sex, height, and optional current weight to see all six ideal-weight formulas plus the healthy BMI range.

3Target BMI: enter height, current weight, and a target BMI to see the exact weight needed and the gap from your current weight.

4Weight by Frame Size: enter sex, height, and frame size to see the traditional weight-by-frame guideline for your build.

How to understand and use this calculator

Quick Answer

The most validated formula (Devine):

Men: 50.0 kg + 2.3 kg for each inch over 5 feet
Women: 45.5 kg + 2.3 kg for each inch over 5 feet

Quick examples (Devine formula):

5'6" female: ideal weight ≈ 59.3 kg (130.7 lb)
5'10" male: ideal weight ≈ 73.0 kg (160.9 lb)
5'5" female: ideal weight ≈ 57.0 kg (125.7 lb)

Healthy BMI range: 18.5–24.9 — remember this is a weight range, not a single number.

How much are you supposed to weigh? It depends on your height, sex, and body composition. Use the calculator above to get your personalized range from all six formulas at once.

Use the Ideal Weight Calculator

This calculator has three modes, matching the three things people actually need from an ideal-weight tool:

Compare Formulas — enter your sex, height, and (optionally) your current weight to see all six ideal-weight formulas plus your healthy BMI range at once.
Target BMI — enter your height and current weight, pick a target BMI, and see exactly how much you need to gain or lose to reach it.
Weight by Frame Size — enter your sex, height, and frame size (small, medium, or large) to see the traditional weight-by-frame guideline for your build.

Example input (Compare Formulas mode): Female, height 5'6" (66 in), current weight 150 lb.

Example input (Target BMI mode): Female, height 5'6", current weight 150 lb, target BMI 21.7.

Output: Target weight = 61.0 kg (134.5 lb) • You would need to lose about 15.5 lb to reach a BMI of 21.7.

What Is Ideal Body Weight?

Ideal Body Weight (IBW) is an estimate of what a healthy person of your height and sex should weigh. It is not a strict number but a general clinical guideline.

Key points:

Ideal weight varies by height and sex.
It's an estimate, not a precise measurement.
It doesn't account for muscle mass or body composition.
It is useful for setting health and fitness goals, not for diagnosing anyone.

How much are you supposed to weigh depends on:

Your height — taller people generally weigh more.
Your sex — men typically carry more lean mass than women at the same height.
Your body composition — muscle is denser than fat, so it weighs more per unit of volume.
Your frame size — small, medium, and large frames shift the healthy range up or down.

Two people of the same height and sex can have very different healthy weights depending on their body composition — ideal weight is a starting point, not a rule.

Why Ideal Weight Matters

Being underweight carries its own risks: weakened immunity, lower bone density, hormonal disruptions that can affect fertility, and persistent fatigue.

Being overweight carries related risks: higher blood pressure and cholesterol, a strong correlation with type 2 diabetes, added strain on joints, and a higher likelihood of sleep apnea.

This is why the calculator shows a range rather than one number — health outcomes track a band of healthy weights, not a single exact figure.

The Devine Formula — Most Validated Method

The formula:

Men: 50.0 kg + 2.3 kg per inch over 5 feet
Women: 45.5 kg + 2.3 kg per inch over 5 feet

Step-by-step example 1: 5'6" female

Step 1 — convert height to inches: 5'6" = 66 in.
Step 2 — inches over 5 feet: 66 − 60 = 6 in.
Step 3 — apply the formula: 45.5 + (2.3 × 6) = 45.5 + 13.8 = 59.3 kg (130.7 lb).

Step-by-step example 2: 5'10" male

Step 1 — convert height to inches: 5'10" = 70 in.
Step 2 — inches over 5 feet: 70 − 60 = 10 in.
Step 3 — apply the formula: 50.0 + (2.3 × 10) = 50.0 + 23.0 = 73.0 kg (160.9 lb).

Other Ideal Weight Formulas Compared

Besides Devine, four other formulas are commonly cited, all using the same "kg + kg per inch over 5 feet" structure except Broca and Lorentz, which work directly from height in centimeters:

Robinson (1983): Men 52.0 kg + 1.9 kg/inch over 5'; Women 49.0 kg + 1.7 kg/inch over 5'. A modification of Devine.
Miller (1983): Men 56.2 kg + 1.41 kg/inch over 5'; Women 53.1 kg + 1.36 kg/inch over 5'. Another Devine modification with a gentler slope.
Hamwi (1964): Men 48.0 kg + 2.7 kg/inch over 5'; Women 45.5 kg + 2.2 kg/inch over 5'. Common in clinical nutrition settings.
Broca: height (cm) − 100, for both sexes. Simple, but less accurate — it ignores sex entirely.
Lorentz: Men (height − 100) − (height − 150)/4; Women (height − 100) − (height − 150)/2. Popular in parts of Europe.

All six formulas for a 5'6" (167.6 cm) female:

Devine: 59.3 kg (130.7 lb)
Robinson: 59.2 kg (130.5 lb)
Miller: 61.3 kg (135.1 lb)
Hamwi: 58.7 kg (129.4 lb)
Broca: 67.6 kg (149.1 lb)
Lorentz: 58.8 kg (129.7 lb)

All six formulas for a 5'10" (177.8 cm) male:

Devine: 73.0 kg (160.9 lb)
Robinson: 71.0 kg (156.5 lb)
Miller: 70.3 kg (155.0 lb)
Hamwi: 75.0 kg (165.3 lb)
Broca: 77.8 kg (171.5 lb)
Lorentz: 70.9 kg (156.2 lb)

BMI and Ideal Weight — The Healthy Range

BMI (Body Mass Index) measures body weight relative to height. It is the basis for the "healthy range" shown alongside every formula result.

The formula: BMI = Weight (kg) ÷ Height (m)²

BMI categories:

Below 18.5 — Underweight
18.5–24.9 — Normal (healthy)
25.0–29.9 — Overweight
30.0 and above — Obese

Finding your healthy weight range from BMI:

Step 1 — convert height to meters.
Step 2 — minimum healthy weight = 18.5 × (height in meters)².
Step 3 — maximum healthy weight = 24.9 × (height in meters)².

Worked example: 5'6" female (167.64 cm = 1.6764 m)

Minimum: 18.5 × 1.6764² = 18.5 × 2.8103 = 52.0 kg (114.6 lb)
Maximum: 24.9 × 1.6764² = 24.9 × 2.8103 = 70.0 kg (154.3 lb)
Healthy range: 52.0–70.0 kg (114.6–154.3 lb)

Solving Backward: Finding the Weight to Hit a Target BMI

Formula: Target weight (kg) = Target BMI × Height (m)²

Worked example: height 5'6" (1.6764 m), target BMI 21.7 (a common "healthy midpoint" target).

Target weight = 21.7 × 1.6764² = 21.7 × 2.8103 = 61.0 kg (134.5 lb).
If your current weight is 150 lb (68.0 kg), you would need to lose 68.0 − 61.0 = 7.0 kg (≈15.5 lb) to reach BMI 21.7.

This is especially useful for setting a concrete, realistic goal weight instead of aiming vaguely at "somewhere in the healthy range." Pair it with the BMI Calculator to track your BMI as you go.

Weight Guidelines by Height, Sex, and Frame Size

How to estimate your frame size: measure your wrist circumference.

Small: wrist under 6.5" (women) or under 6.75" (men)
Medium: wrist 6.5"–7.5" (women) or 6.75"–7.5" (men)
Large: wrist over 7.5"

Reference points for women (medium frame):

5'0": 105–115 lb
5'4": 115–125 lb
5'6": 125–135 lb
5'8": 130–140 lb
5'10": 135–145 lb

Reference points for men (medium frame):

5'6": 135–145 lb
5'8": 140–150 lb
5'10": 145–155 lb
6'0": 150–160 lb
6'2": 155–165 lb

How to Calculate Ideal Weight in Excel

Every formula on this page is a one-line spreadsheet formula. Put height in inches in cell B1 and sex ("M" or "F") in cell B2.

Devine formula: =IF(B2="M", 50+2.3*MAX(B1-60,0), 45.5+2.3*MAX(B1-60,0)) — result in kg; multiply by 2.2046226218 to convert to lb.

Robinson formula: =IF(B2="M", 52+1.9*MAX(B1-60,0), 49+1.7*MAX(B1-60,0))

Miller formula: =IF(B2="M", 56.2+1.41*MAX(B1-60,0), 53.1+1.36*MAX(B1-60,0))

Hamwi formula: =IF(B2="M", 48+2.7*MAX(B1-60,0), 45.5+2.2*MAX(B1-60,0))

Broca formula (height in cm in B3): =B3-100

Lorentz formula (height in cm in B3): =IF(B2="M", (B3-100)-(B3-150)/4, (B3-100)-(B3-150)/2)

Healthy BMI weight range (height in meters in B4): Minimum =18.5*B4^2, Maximum =24.9*B4^2

Target weight for a goal BMI (target BMI in B5): =B5*B4^2

BMI itself (weight in kg in B6): =B6/B4^2 — or in imperial units, with height in inches in B1 and weight in lb in B6: =703*B6/B1^2

Real-World Ideal Weight Examples

Example 1 — 5'2" female, small frame: Devine ≈ 50.1 kg (110.5 lb). Weight-by-frame guideline (small): roughly 105–115 lb, comparable to the Devine estimate.

Example 3 — 5'9" male at 200 lb wanting BMI 24: target weight = 24 × (1.7526 m)² = 24 × 3.0716 = 73.7 kg (162.5 lb). He would need to lose about 37.5 lb to reach BMI 24.

Practice Problems

Problem 1: What is the Devine ideal weight for a 5'6" female? Solution: height = 66 in, 6 in over 5 ft. 45.5 + (2.3 × 6) = 45.5 + 13.8 = 59.3 kg (130.7 lb).

Problem 2: What is the Devine ideal weight for a 5'10" male? Solution: height = 70 in, 10 in over 5 ft. 50.0 + (2.3 × 10) = 50.0 + 23.0 = 73.0 kg (160.9 lb).

Problem 4: What is the Devine ideal weight for a 5'5" female? Solution: height = 65 in, 5 in over 5 ft. 45.5 + (2.3 × 5) = 45.5 + 11.5 = 57.0 kg (125.7 lb).

Answers: 1) 59.3 kg (130.7 lb) — 2) 73.0 kg (160.9 lb) — 3) 50.4–67.9 kg (111.2–149.6 lb) — 4) 57.0 kg (125.7 lb) — 5) target 151.2 lb, lose 38.8 lb.

Common Ideal Weight Mistakes

Treating ideal weight as a strict number. Mistake: believing you must weigh exactly the formula result. Fix: use it as a midpoint of a reasonable range, not a hard target.
Ignoring muscle mass. Mistake: not accounting for muscle, which is denser than fat. Fix: cross-check with the Body Fat Calculator before assuming you need to lose weight.
Using the wrong formula for your sex. Mistake: applying the male formula to a female height or vice versa. Fix: always confirm the sex-specific constant before calculating by hand.
Ignoring frame size. Mistake: using one number for every build. Fix: check the Weight by Frame Size mode above, especially if you have a notably small or large frame.
Focusing only on weight. Mistake: ignoring other health markers. Fix: consider blood pressure, cholesterol, and fitness level alongside weight — pair this tool with the BMI Calculator and BMR Calculator.
Applying adult formulas to children or teens. Mistake: these formulas assume a fully grown adult skeleton. Fix: use pediatric growth charts instead.
Confusing weight loss with fat loss. Mistake: chasing a lower number on the scale. Fix: focus on body composition — the Calorie Calculator can help set a realistic, sustainable deficit.
Skipping medical guidance. Mistake: making health decisions from a calculator alone. Fix: use these numbers as a conversation starter with a doctor or registered dietitian, not a replacement for one.

Ideal Weight vs. BMI vs. Body Fat vs. Frame Size

Ideal weight formulas (Devine, Robinson, Miller, Hamwi, Broca, Lorentz) give a single-point weight estimate from height and sex only.

BMI gives a healthy weight *range* from height alone, and is the basis for the range shown next to every formula on this page. Check it directly with the BMI Calculator.

Frame size adjusts the expected weight up or down for skeletal build, independent of muscle or fat — see the Weight by Frame Size mode above.

What This Calculator Can and Cannot Do

This calculator CAN help with:

Estimating ideal weight using six validated formulas at once
Finding your healthy BMI weight range
Solving backward for the weight needed to hit a target BMI
Checking the traditional weight-by-frame-size guideline for any height
Setting realistic health and fitness goals

This calculator CANNOT do:

Account for muscle mass or body composition directly
Provide personalized medical advice
Replace a doctor's assessment or diagnostic evaluation
Determine whether you specifically should gain or lose weight
Account for pregnancy or existing medical conditions
Apply to children or teenagers — these formulas assume a fully grown adult

Final Summary

Remember the key formulas:

Devine (men): 50.0 kg + 2.3 kg/inch over 5 feet
Devine (women): 45.5 kg + 2.3 kg/inch over 5 feet
Healthy BMI range: 18.5–24.9
Target weight for a goal BMI: Target BMI × Height (m)²

Quick reference:

5'6" female: ≈59.3 kg (130.7 lb) Devine, 52.0–70.0 kg (114.6–154.3 lb) healthy range
5'10" male: ≈73.0 kg (160.9 lb) Devine, 58.5–78.7 kg (128.9–173.5 lb) healthy range

Start now — enter your height and sex above to see your personalized range across all three modes, completely free.

Related concepts

Devine Formula

The most medically validated ideal-weight formula, used clinically for medication dosing calculations.

Body Mass Index (BMI)

A weight-to-height ratio that defines the healthy weight range shown alongside every ideal-weight formula.

Frame Size

A classification of skeletal build (small, medium, large) that shifts the expected healthy weight up or down.

Lean Body Mass

The weight of everything in your body except fat — muscle, bone, and water — which weight-only formulas cannot measure directly.

Frequently Asked Questions

What is an ideal weight calculator?+

An ideal weight calculator estimates what a healthy person of your height and sex should weigh, using validated clinical formulas such as Devine, Robinson, Miller, and Hamwi.

How much am I supposed to weigh?+

It depends on your height, sex, and body composition. Use the Compare Formulas mode above to see your personalized range across six formulas plus the healthy BMI range.

What is the average weight of a 5'5" female?+

According to the Devine formula, the ideal weight for a 5'5" female is about 57.0 kg (125.7 lb). The healthy BMI weight range for that height is approximately 50.4–67.9 kg (111.2–149.6 lb).

What is the ideal weight for a 5'6" female?+

According to the Devine formula, the ideal weight for a 5'6" female is about 59.3 kg (130.7 lb). The healthy BMI weight range is approximately 52.0–70.0 kg (114.6–154.3 lb).

What is the most accurate ideal weight formula?+

The Devine formula is the most widely used and medically validated, especially for medication dosing. Robinson, Miller, and Hamwi are close alternatives that shift the estimate by a few kilograms.

What is a healthy BMI range?+

A healthy BMI range is 18.5 to 24.9. Below 18.5 is considered underweight, 25.0–29.9 overweight, and 30.0 and above obese.

How do I calculate my ideal weight?+

How much weight do I need to gain or lose to reach a healthy BMI?+

Switch to the Target BMI mode, enter your height, current weight, and target BMI, and the calculator shows the exact target weight and the gap from your current weight.

Can ideal weight calculators be wrong?+

They're estimates, not measurements. They don't account for muscle mass, frame size, or individual variation, so treat the result as a starting point, not a verdict.

Should I use ideal weight for weight loss goals?+

Use it as a general guideline alongside your healthy BMI range, but focus on overall health, body composition, and fitness rather than hitting one exact number.

What if I have a large or small frame?+

Is ideal weight the same as healthy weight?+

Not exactly. Ideal weight (from formulas like Devine) is a single-point estimate. Healthy weight is a range based on BMI (18.5–24.9) for your height — usually a wider and more realistic target.

Does ideal weight change with age, or apply during pregnancy or to children?+

These formulas assume a fully grown adult and do not adjust for age, and they do not apply during pregnancy or to children and teenagers, who should be assessed with pediatric growth charts instead.

Is this ideal weight calculator free?+

Yes — completely free, with no registration required.

Ideal Weight Calculator

Inputs

Results

Ideal weight formulas

How the calculation works

Learn more about this calculation

Ideal Weight Range: Height-Based Estimates and Their Limits

BMI Calculation Guide: Formula, Ranges, and Limits

BMI Calculator

Body Fat Calculator

BMR Calculator

Calorie Calculator

Protein Calculator

Macro Calculator

Ideal Weight Calculator

Inputs

Results

Key output metrics

All six ideal weight formulas

Healthy BMI weight range

How to understand and use this calculator

Quick Answer

Use the Ideal Weight Calculator

What Is Ideal Body Weight?

Why Ideal Weight Matters

The Devine Formula — Most Validated Method

Other Ideal Weight Formulas Compared

BMI and Ideal Weight — The Healthy Range

Solving Backward: Finding the Weight to Hit a Target BMI

Weight Guidelines by Height, Sex, and Frame Size

How to Calculate Ideal Weight in Excel

Real-World Ideal Weight Examples

Practice Problems

Common Ideal Weight Mistakes

Ideal Weight vs. BMI vs. Body Fat vs. Frame Size

What This Calculator Can and Cannot Do

Final Summary

Related concepts

Frequently Asked Questions

Ideal weight formulas

How the calculation works

Learn more about this calculation

Ideal Weight Range: Height-Based Estimates and Their Limits

BMI Calculation Guide: Formula, Ranges, and Limits

BMI Calculator

Body Fat Calculator

BMR Calculator

Calorie Calculator

Protein Calculator

Macro Calculator

Key output metrics

All six ideal weight formulas

Healthy BMI weight range

How to understand and use this calculator

Quick Answer

Use the Ideal Weight Calculator

What Is Ideal Body Weight?

Why Ideal Weight Matters

The Devine Formula — Most Validated Method

Other Ideal Weight Formulas Compared

BMI and Ideal Weight — The Healthy Range

Solving Backward: Finding the Weight to Hit a Target BMI

Weight Guidelines by Height, Sex, and Frame Size

How to Calculate Ideal Weight in Excel

Real-World Ideal Weight Examples

Practice Problems

Common Ideal Weight Mistakes

Ideal Weight vs. BMI vs. Body Fat vs. Frame Size

What This Calculator Can and Cannot Do

Final Summary

Related concepts

Frequently Asked Questions