Find your ideal body weight based on your height, gender, and body frame size using five recognised medical formulas.
✔ Healthy weight range • ✔ Multiple formulas • ✔ Metric & Imperial • ✔ Instant calculation
Body frame size refers to your natural bone structure rather than body fat or muscle. People with a larger frame generally have heavier bones and may naturally weigh more than someone of the same height with a smaller frame.
This Ideal Weight Calculator estimates a healthy body weight range based on your height, gender, age, and body frame size. It uses several widely recognised formulas, including the Devine, Robinson, and Miller methods, together with healthy BMI ranges to provide a realistic weight estimate.
Rather than focusing on a single number, the calculator provides a healthy weight range that may be more useful for long-term health and fitness goals.
There is no single perfect weight for every person. Different medical formulas have been developed over the years to estimate healthy body weight based primarily on height and gender.
This calculator combines multiple recognised methods to provide a balanced estimate rather than relying on just one formula.
The result also takes body frame size into account, as people with larger bone structures may naturally weigh more while remaining healthy.
The Devine Formula was developed in 1974 by Dr. Ben J. Devine to estimate an ideal body weight for medication dosing. Today, it remains one of the most widely recognised methods for estimating healthy body weight in both clinical practice and online calculators.
The formula is based on a person's height and gender and assumes an average body frame. In this calculator, the result can also be adjusted for small or large body frame sizes to provide a more personalised estimate.
Although originally designed for medical use, the Devine Formula is still commonly used as a general guide for determining healthy body weight.
The Robinson Formula was introduced in 1983 as an alternative to the Devine Formula. It generally predicts a slightly lower ideal body weight and is considered by many healthcare professionals to produce realistic estimates for average adults.
Like the Devine method, the Robinson Formula uses only height and gender. It does not directly account for body composition, muscle mass, or age.
Many ideal weight calculators include the Robinson Formula because it often provides balanced results that fall comfortably within healthy BMI ranges.
The Miller Formula, introduced in 1983, is another widely used method for estimating ideal body weight. Compared with the Devine and Robinson formulas, it tends to produce slightly different values depending on height, making it useful when comparing multiple estimation methods.
The Miller Formula also estimates ideal weight using height and gender and is frequently included alongside other recognised formulas to provide a more balanced recommendation.
The Hamwi Formula was introduced in 1964 by Dr. G. J. Hamwi as a simple method for estimating ideal body weight. It became widely used in hospitals, nutrition, and clinical practice because of its straightforward approach based on height and gender.
Unlike some newer formulas, the Hamwi Formula does not account for body composition, muscle mass, or age. However, it remains one of the most recognised methods for estimating a healthy body weight and is still commonly referenced by healthcare professionals.
Because the Hamwi Formula generally produces slightly higher estimates than some other methods, it is particularly useful when comparing multiple ideal weight formulas. This calculator includes the Hamwi Formula as part of its combined recommendation to provide a balanced estimate rather than relying on a single equation.
The Lemmens Formula was published in 2005 and takes a different approach from the other ideal weight formulas. Instead of calculating ideal weight using inches over 5 feet, it is based on a Body Mass Index (BMI) of 22, which is close to the centre of the healthy BMI range for most adults.
The formula estimates ideal body weight using only a person's height and applies equally to males and females. It is calculated as:
Because the Lemmens Formula is BMI-based rather than height-inches based, it often produces results that differ slightly from the Devine, Robinson, Miller, and Hamwi formulas. Including it provides an additional perspective when estimating a healthy body weight.
This calculator combines the Lemmens Formula with four other recognised medical formulas to create a consensus estimate that is generally more reliable than relying on any single method alone.
Because each formula was developed using different research populations and assumptions, no single method is considered perfect. This calculator combines the Devine, Robinson, Miller, Hamwi, and Lemmens formulas to produce a balanced recommendation rather than relying on only one equation.
Because of these factors, two people of the same height may have different healthy weights.
Many healthcare professionals use BMI as a general guide when assessing healthy body weight.
This is the weight range corresponding to a Body Mass Index (BMI) between 18.5 and 24.9, which is generally considered healthy for most adults.
| BMI | Category |
|---|---|
| Below 18.5 | Underweight |
| 18.5 – 24.9 | Healthy Weight |
| 25.0 – 29.9 | Overweight |
| 30+ | Obese |
The ideal weight calculated by this tool generally falls within the healthy BMI category.
Many people focus on reaching one exact target weight, but healthy weight is usually better viewed as a range.
Factors such as muscle mass, hydration, body composition, and genetics can all influence body weight without necessarily affecting overall health.
For example, an athlete with significant muscle mass may weigh more than the average recommendation while remaining very healthy.
Ideal weight formulas provide estimates and should not be considered strict medical targets.
These formulas do not directly measure:
For a more complete picture of your health, consider using BMI, body fat percentage, waist measurements, and advice from healthcare professionals.
Is this calculator accurate?
This calculator provides a reliable estimate by combining five widely recognised medical formulas rather than relying on a single method. However, no ideal weight formula can account for individual factors such as muscle mass, body fat percentage, genetics, or overall health.
Why does the calculator show a recommended weight and a BMI range?
The recommended weight is an average of five recognised medical formulas adjusted for your selected body frame size. The healthy BMI range shows the wider weight range generally associated with a Body Mass Index between 18.5 and 24.9.
Why is a healthy weight range better than one exact number?
Healthy body weight naturally varies between individuals. A range provides a more realistic target because body composition, muscle mass, hydration, and genetics all influence weight.
Which ideal weight formula is the most accurate?
There is no universally accepted "best" formula. Different methods were developed using different research populations and assumptions. This calculator combines the Devine, Robinson, Miller, Hamwi, and Lemmens formulas to provide a balanced estimate.
Why do the formulas give different results?
Each formula uses a slightly different mathematical approach. Some estimate higher ideal weights, while others estimate lower values. Averaging several recognised formulas helps reduce the influence of any single method.
Should I aim for the exact recommended weight?
Not necessarily. The recommended weight is intended as a useful guide rather than a strict target. Remaining within a healthy weight range is generally more important than reaching one exact number.
Can athletes have a higher healthy weight?
Yes. Athletes and people with greater muscle mass often weigh more than standard recommendations while maintaining a healthy body fat percentage.
Does age affect ideal weight?
Age can influence body composition and metabolism over time. However, the recognised formulas used in this calculator are primarily based on height and gender rather than age.
Does body frame size make a difference?
Yes. People with a larger bone structure generally weigh more than those with a smaller frame of the same height. This calculator adjusts the final recommendation by approximately 5% for small and large body frames.
Can I use this calculator for children?
No. This calculator is designed for adults. Healthy weight assessments for children and teenagers should use age- and sex-specific growth charts rather than adult formulas.
Can this calculator help with weight loss?
It can provide a useful long-term weight goal, but it should not replace personalised medical or nutritional advice. Healthy eating, regular exercise, and guidance from a healthcare professional remain the best approach for managing body weight.
Should I rely only on my ideal weight?
No. Ideal weight is only one indicator of health. It should be considered alongside BMI, waist circumference, body fat percentage, physical fitness, blood pressure, and advice from healthcare professionals.
Health-related information is based on publicly available guidance and commonly accepted medical and health calculation methods.
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Last Updated: August 2026