Health calculators

Healthy Weight Calculator

Updated Sep 4, 2026 By Jehan Wadia
Unit System
Height is entered in feet & inches (US) or centimetres (Metric). Every weight result is shown in both pounds and kilograms.
Your Details
Biological Sex required
Sex is used only to apply the appropriate IBW formula. These formulas were developed using biological sex as a variable.
Enter a whole number from 2 to 80.
Height required
Supported range: 5 ft 0 in to 7 ft 0 in (152.4 cm – 213.4 cm).

This calculator may not apply to you if:

Your Healthy Weight Results

Formula Average (4 IBW formulas)
 
Healthy BMI Weight Range (18.5–24.9)
 
Inputs Used
 
Multi-Formula Comparison
Healthy weight estimates by formula for your inputs.
Formula Year Healthy Weight vs. Formula Average
Visual Range

Formula Comparison Chart
What Your Numbers Mean
    Step-by-Step Solution

    Introduction

    The Healthy Weight Calculator shows you a weight range that fits your height, sex, and age. Type in your height in feet and inches or in centimeters, pick male or female, and add your age. The tool then gives you a healthy weight in both pounds and kilograms.

    This calculator uses four trusted ideal body weight formulas: Hamwi (1964), Devine (1974), Robinson (1983), and Miller (1983). The coefficients are those printed in a review of ideal-body-weight equations.1 Each one gives a slightly different number because each was built from a different group of people. We show all four, plus the average, so you can see the full picture instead of one single number.

    You also get your healthy BMI weight range, based on a BMI of 18.5 to 25. A chart, a range bar, and step-by-step math help you see how each number was found.

    Keep in mind that these numbers are a guide, not a rule. They do not measure muscle, bone, or body fat. An athlete with lots of muscle may weigh more and still be healthy. Use this tool as a starting point, then talk with your doctor about the right weight goal for you.

    How to use our Healthy Weight Calculator

    Enter your unit system, sex, age, and height. The calculator shows your healthy weight from four ideal body weight formulas, their average, and your healthy BMI weight range in both pounds and kilograms.

    Unit System: Pick "US / Imperial" to type your height in feet and inches, or pick "Metric" to type it in centimetres. Weight results always show both pounds and kilograms.

    Biological Sex: Choose Male or Female. Each choice uses its own set of formula numbers, so the results change.

    Age (years): Type your age as a whole number from 2 to 80. Age does not change the math, but it flags notes for kids under 18 and adults 65 and older.

    Height (feet and inches): In US mode, type your feet in the first box and your inches in the second. You can use decimals for inches, like 10.5.

    Height (cm): In Metric mode, type your height in centimetres, such as 177.8. Decimals are fine.

    Calculate and Reset: Click Calculate to see your results, chart, and step-by-step math. Click Reset to clear your entries and start again.

    What Is a Healthy Weight?

    A healthy weight is a weight range that keeps your body working well and lowers your risk of problems like type 2 diabetes, high blood pressure, and heart disease. There is no single perfect number. Your height, frame size, muscle, age, and health history all change what is right for you. Body shape matters too.

    Ideal Body Weight (IBW) Formulas

    Doctors have used simple math formulas for years to guess a healthy weight from height and sex. Each one starts with a base weight for a person who is 5 feet (60 inches) tall, then adds weight for every inch above that. Because each formula came from a different study and time period, they give slightly different answers.

    • Hamwi (1964) – the oldest formula, first made to help set food plans for people with diabetes.
    • Devine (1974) – built to help set medicine doses.1 It is still the most common one in hospitals.
    • Robinson (1983) – a newer update of Devine that gives lower numbers.
    • Miller (1983) – has a higher starting weight but adds less per inch.

    Averaging all four gives a smoother middle number instead of trusting just one formula. In clinical settings where a patient weighs far more than their IBW, staff often switch to the Adjusted Body Weight Calculator for dosing math.

    Healthy BMI Weight Range

    BMI (body mass index) compares your weight to your height. Health agencies put the normal BMI range at 18.5 to 24.9, with overweight starting at 25.0, and this calculator uses 24.9 as the top of the band.2 Turning that range into pounds or kilograms gives you a weight range instead of one target. Most people do well somewhere inside it. People with more muscle or bigger bones often sit near the top of the range.

    What BMI and IBW Miss

    These numbers only use height and weight. They cannot tell muscle from fat, and they do not look at where fat sits on your body. That means:

    • Athletes with heavy muscle may look "overweight" on paper but be very healthy. The Body Fat Calculator gives a clearer read for muscular builds.
    • Older adults may lose muscle and look fine on paper while carrying too much fat.
    • Belly fat matters a lot for health risk, so waist size is a useful second check.

    Losing Weight in a Safe Way

    If you are above your healthy range, you do not need to hit the exact ideal number to feel better. Losing even a modest share of your body weight can lower blood pressure, blood sugar, and cholesterol; the National Heart, Lung, and Blood Institute's guide sets an initial goal of about 10 percent.2

    A safe pace is about 1 to 2 pounds per week, which the same guide ties to eating 500 to 1,000 fewer calories a day than you burn.2 That is roughly 0.5 to 1 kg a week, alongside regular walking, strength work, and good sleep. Slow, steady change is easier to keep than a crash diet.

    When to Ask a Professional

    Talk to a doctor or dietitian before starting a weight plan if you are under 18, over 65, pregnant, breastfeeding, taking medicine that changes weight, or living with a health condition. They can look at your body fat, muscle, blood work, and habits, which no formula can do.


    Formulas used

    Height conversion to inches and metres
    h_{in} = 12 \times ft + in, \qquad h_{cm} = h_{in} \times 2.54, \qquad h_{m} = h_{in} \times 0.0254
    Inches above 5 feet (60 in)
    h_{>60} = \max(0,\; h_{in} - 60)
    General ideal body weight (IBW) formula
    IBW_{kg} = B + k \times h_{>60}
    IBW coefficients by formula and sex (base B in kg, k in kg/inch) 1
    \begin{array}{lcc} \text{Formula} & \text{Male } (B,\,k) & \text{Female } (B,\,k) \\ \text{Hamwi (1964)} & (48.0,\; 2.7) & (45.5,\; 2.2) \\ \text{Devine (1974)} & (50.0,\; 2.3) & (45.5,\; 2.3) \\ \text{Robinson (1983)} & (52.0,\; 1.9) & (49.0,\; 1.7) \\ \text{Miller (1983)} & (56.2,\; 1.41) & (53.1,\; 1.36) \end{array}
    Average of the four IBW formulas
    IBW_{avg} = \frac{IBW_{Hamwi} + IBW_{Devine} + IBW_{Robinson} + IBW_{Miller}}{4}
    Healthy BMI weight range (BMI 18.5-25.0)
    W_{min} = 18.5 \times h_{m}^2, \qquad W_{max} = 25.0 \times h_{m}^2
    Kilograms to pounds conversion
    W_{lb} = \frac{W_{kg}}{0.45359237}
    Difference of each formula from the average
    \Delta = IBW_{formula} - IBW_{avg}

    Frequently asked questions

    Should I aim for the formula average or the BMI range?

    The BMI range is the better goal for most people. It gives a band of healthy weights instead of one exact number.

    The formula average is one single point inside or near that band. Use it as a rough middle marker, not a target you must hit.

    Why is my formula average lower than my healthy BMI range?

    The four ideal body weight formulas add only 1.4 to 2.7 kg for each inch above 5 feet. BMI grows faster with height.

    So for tall people, the formula average often sits near the bottom of the BMI band or just under it. That is normal and does not mean you are overweight.

    Why doesn't my age change the numbers?

    The four formulas use only height and sex. Age does not go into the math.

    Your age is used to show warning notes instead. If you are under 18 or 65 and over, the tool flags that the results may not fit you well.

    How much should a 5'10" man weigh?

    For a 5'10" male, the four formulas give about 155 to 165 lbs (70.3 to 75.0 kg). The average is close to 159 lbs (72.3 kg).

    His healthy BMI weight range is wider: about 129 to 174 lbs (58.5 to 79.0 kg).

    How much should a 5'4" woman weigh?

    For a 5'4" female, the four formulas give about 120 to 129 lbs (54.3 to 58.5 kg), with an average near 123 lbs (55.8 kg).

    Her healthy BMI weight range runs from about 108 to 146 lbs (48.9 to 66.1 kg).

    What does the "vs. Formula Average" column mean?

    It shows how far each formula sits from the average of all four. A plus sign means that formula is higher than the average. A minus sign means it is lower.

    A big gap tells you the formulas do not agree closely for your height.

    Does my frame size change my healthy weight?

    Yes, but these formulas do not measure it. Someone with wide shoulders and thick bones can weigh more and still be healthy.

    If you have a large frame, aim nearer the top of your BMI range. If you have a small frame, aim lower.

    Will my result change if I switch between US and Metric?

    No. The tool converts your height for you, and the math stays the same.

    Only the order of the units changes. Every weight is shown in both pounds and kilograms either way.

    Is it bad if I weigh more than my ideal body weight?

    Not always. These formulas came from old studies and often read low, especially for muscular people.

    Check your waist size and body fat too. If your weight sits inside the healthy BMI band and your waist is under half your height, you are likely fine.

    Can I use these numbers for medicine doses?

    No. Doctors do use the Devine formula for some drug doses, but they adjust it with lab tests, kidney function, and body fat.

    This tool is for personal health planning only. Never change a dose on your own.

    How often should I check my healthy weight?

    Once is usually enough. Your healthy range only changes if your height changes, which happens slowly with age.

    Weigh yourself weekly instead, at the same time of day, to track progress toward that range.


    Sources

    1. Peterson CM, Thomas DM, Blackburn GL, Heymsfield SB. Universal equation for estimating ideal body weight and body weight at any BMI. American Journal of Clinical Nutrition. 2016;103(5):1197-1203. doi:10.3945/ajcn.115.121178. Accessed September 4, 2026.
    2. The Practical Guide: Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. National Heart, Lung, and Blood Institute. 2000;NIH Publication No. 00-4084. Accessed September 4, 2026.