Ideal Weight Calculator

Our Ideal Weight Calculator estimates your ideal body weight (IBW) based on your height, gender, and age. For decades, health and fitness experts have sought the most accurate way to calculate IBW using mathematical equations.

Several classic formulas remain highly popular today. Our Ideal Weight Calculator presents these results side-by-side, allowing you to easily compare them.

What is my Ideal Weight?

Many people strive to lose weight—some for health reasons, and others to achieve what society considers an "ideal" body. Often, this ideal is shaped by what we see in media advertising, including social networks, television, movies, and magazines.

While ideal body weight is frequently linked to visual appeal, IBW was originally introduced to estimate medication dosages. Medical professionals discovered that body weight plays a critical role in how the body metabolizes certain drugs.

The formulas used to calculate IBW have nothing to do with how a person looks at a given weight. Instead, they were designed to improve clinical dosage accuracy. Today, IBW is also widely used in sports to classify athletes into appropriate weight categories.

However, the standard IBW scale is not perfect. It does not account for a person’s body fat percentage or muscle mass, meaning it is not a comprehensive metric of overall health. Depending on the IBW formula used, even the most highly active and fit athletes might be incorrectly categorized as overweight.

Ultimately, it is impossible to pinpoint exactly how much a specific individual should weigh. Healthy weight varies significantly from person to person. No single measurement—whether IBW, Body Mass Index (BMI), or another metric—can definitively establish the perfect weight for optimal health. These figures serve simply as general guidelines.

Prioritizing regular exercise, a balanced diet of whole foods, and adequate sleep is far more critical than chasing a specific number on a scale. Committing to a healthy lifestyle should always be your primary goal.

Several key variables influence your ideal weight. While factors like genetics, underlying health conditions, and fat distribution play a role, the most significant determinants are detailed below.

Age

In theory, age shouldn't heavily impact your IBW once you stop growing—typically around 14–15 years old for girls and 16–17 years old for boys. Interestingly, as people age, they tend to lose height; by age 70, men and women can expect to lose about 1.5 and 2 inches, respectively.

As we age, muscle mass naturally decreases while body fat accumulates more easily. While this is a normal biological process, you can mitigate the effects of aging by maintaining healthy habits, such as eating a nutrient-rich diet, exercising regularly, managing stress, and getting quality sleep.

Gender

On average, females weigh less than males but possess a naturally higher body fat percentage. Conversely, the male body carries more muscle mass, and since muscle weighs more than fat by volume, this increases overall weight. Women also typically have lower bone density than men, and men generally stand taller.

Height

The taller you are, the more muscle mass and body fat you naturally carry, resulting in a higher overall weight. Even at comparable heights, a male will typically weigh 10–20% more than a female of the same stature.

Body Frame Size

Your body frame size is another crucial factor that influences ideal weight calculations. Health and fitness specialists typically classify body frames into three categories: small-boned, medium-boned, and large-boned. As detailed below, you can determine your frame size by measuring your wrist circumference in relation to your height.

Here are the standard calculations, including both imperial and metric units (with metric units rounded to the nearest tenth):

For Women

For a height under 5'2" (157.5 cm):

• Small-boned: wrist size less than 5.5" (14.0 cm)
• Medium-boned: wrist size 5.5" to 5.75" (14.0 cm to 14.6 cm)
• Large-boned: wrist size over 5.75" (14.6 cm)

For a height between 5'2" and 5' 5" (157.5 cm to 165.1 cm):

• Small-boned: wrist size less than 6" (15.2 cm)
• Medium-boned: wrist size 6" to 6.25" (15.2 cm to 15.9 cm)
• Large-boned: wrist size over 6.25" (15.9 cm)

For a height over 5' 5" (165.1 cm):

• Small-boned: wrist size less than 6.25" (15.9 cm)
• Medium-boned: wrist size 6.25" to 6.5" (15.9 cm to 16.5 cm)
• Large-boned: wrist size over 6.5" (16.5 cm)

For Men

For a height under 5'2" (157.5 cm):

• Small-boned: wrist size less than 5.75" (14.6 cm)
• Medium-boned: wrist size 5.75" to 6" (14.6 cm to 15.2 cm)
• Large-boned: wrist size over 6" (15.2 cm)

For a height between 5'2" and 5' 5" (157.5 cm to 165.1 cm):

• Small-boned: wrist size less than 6.25" (15.9 cm)
• Medium-boned: wrist size 6.25" to 6.5" (15.9 cm to 16.5 cm)
• Large-boned: wrist size over 6.5" (16.5 cm)

For a height over 5' 5" (165.1 cm):

• Small-boned: wrist size less than 6.5" (16.5 cm)
• Medium-boned: wrist size 6.5" to 7.5" (16.5 cm to 19.1 cm)
• Large-boned: wrist size over 7.5" (19.1 cm)

Two people of the exact same height will weigh differently if one has a larger bone structure. Because body frame size is a vital variable, it directly affects health metrics like IBW and BMI.

Formulas to Help You Find Your Ideal Weight

Scientists originally developed IBW algorithms to simplify medical dosage estimates. Most of these equations follow a similar structural layout: they assign a baseline weight for a height of 5 feet and add a predetermined weight increment for every additional inch. For example, if you are a 5’10" man using the Devine method to calculate your ideal weight, you would add (2.3 × 10) kg to the 50 kg baseline to get 73 kg (or roughly 161 lbs).

The exact values used in these equations vary depending on the scientists who formulated them. Today, the Devine formula remains the most widely recognized method for calculating IBW.

The Formula of J. Hamwi (1964)

48.0 kg + 2.7 kg/inch for the height more than 5 feet - for men

45.5 kg + 2.2 kg/inch for the height more than 5 feet - for women

This formula was originally invented to help physicians prescribe accurate medication dosages.

The Formula of J. Devine (1974)

50.0 kg + 2.3 kg/inch for the height more than 5 feet - for men

45.5 kg + 2.3 kg/inch for the height more than 5 feet - for women

Like the Hamwi method, this was created as a clinical baseline for medical dosing based on height and weight. Over time, the Devine equation evolved into the universal standard for calculating IBW.

The Formula of D. Robinson (1983)

52 kg + 1.9 kg/inch for the height more than 5 feet - for men

49 kg + 1.7 kg/inch for the height more than 5 feet - for women

A modification of the classic Devine formula.

The Formula of R. Miller (1983)

56.2 kg + 1.41 kg/inch for the height more than 5 feet - for men

53.1 kg + 1.36 kg/inch for the height more than 5 feet - for women

Another popular modification of the Devine formula.

BMI in a Healthy Range

The World Health Organization (WHO) recommends a healthy Body Mass Index (BMI) range of 18.5 to 24.9 for both adult men and women. By identifying your target BMI range, you can easily determine a healthy weight for your specific height.

BMI is a highly popular metric utilized alongside IBW calculations. In the medical field, it is frequently used to quickly screen for potential health risks. Generally, a higher BMI indicates an increased likelihood of developing metabolic conditions, such as obesity, type 2 diabetes, and cardiovascular disease.

Today, BMI serves as the official standard for categorizing different levels of obesity. Physicians also use these metrics to counsel patients on personal health risks, particularly if there is a noticeable and gradual increase in their BMI over time.

BMI for Children in a Healthy Range

Since the equations mentioned above are strictly designed for adults (18 years and older), assessing a child's weight requires a different approach. According to the Centers for Disease Control and Prevention (CDC), children and teenagers should maintain a BMI between the 5th and 85th percentiles for their specific age group.

For more information, please consult the official CDC BMI charts below:

CDC BMI chart (boys, age 2 - 20)

CDC BMI chart (girls, age 2 - 20)

Our IBW Calculator Has Several Limitations

Our ideal body weight calculator is meant to serve as a general guide based on popular scientific equations. The results provided do not mean you must rigidly conform to a specific number to achieve your "ideal weight."

Every formula and mathematical model has inherent limitations. Because these equations are designed to apply to the broadest population possible, they cannot be perfectly accurate for every individual. Furthermore, these calculations do not account for physical disabilities, extreme height variations, activity levels, or body composition (your unique ratio of muscle mass to body fat).