What is your ideal weight?

How Much Should I Weigh?

Most people have at some point tried to lose weight, or at least known someone who has. This is largely due to the perception of an "ideal" body weight, which is often shaped by what we see in social media, TV, movies, and magazines. Although ideal body weight (IBW) today is sometimes associated with visual appearance, IBW was originally introduced to estimate drug dosages for medical use — the formulas that calculate it are not related to how a person looks at a given weight. It has since been established that the metabolism of certain drugs is more closely tied to IBW than to total body weight. Today, IBW is also widely used in sports, where many disciplines classify participants by body weight.

IBW is not a perfect measurement. It does not account for the percentages of body fat and muscle in a person's body. This means highly fit, healthy athletes can be classified as overweight based on their IBW. IBW should therefore be viewed as an imperfect reference point — not necessarily an indicator of health, nor a weight that a person must strive to achieve. It is entirely possible to be above or below your IBW and still be in excellent health.

How much a person should weigh is not an exact science. It is highly individual. No single measure — whether IBW, BMI, or any other — can definitively determine a healthy weight for every person. These are references only. Maintaining healthy habits such as regular exercise, eating a variety of whole foods, getting adequate sleep, and managing stress is more important than chasing a specific number from a generalised formula.

Factors That Affect Ideal Weight

Many factors influence what a healthy weight looks like for a given individual. The major ones are listed below. Other contributing factors include health conditions, fat distribution, and genetics.

Age

In theory, age should not be a major determinant of IBW past the ages of 14–15 for girls and 16–17 for boys, after which most people stop growing. It is expected that adult males and females lose approximately 1.5 and 2 inches in height respectively by age 70. As people age, lean muscle mass naturally decreases and it becomes easier to accumulate excess body fat. This process can be slowed by monitoring diet, staying active, managing stress, and getting adequate sleep.

Gender

Generally, females weigh less than males even though they naturally carry a higher percentage of body fat. This is because the male body typically has greater muscle mass, and muscle is denser than fat. Women also tend to have lower bone density, and males tend to be taller than females on average.

Height

The taller a person is, the more muscle mass and body fat they tend to carry, resulting in greater overall weight. A male at a similar height to a female would typically weigh approximately 10–20% more.

Body Frame Size

Body frame size can have a significant impact on ideal weight. Frame size is typically categorised as small, medium, or large boned, and is measured based on wrist circumference relative to height.

Formulas for Finding Ideal Weight

IBW formulas were developed primarily to assist with drug dosage calculations. All formulas share the same structure: a base weight for a height of 5 feet, plus a fixed increment per inch above 5 feet. For example, a 5'10" male using the Devine formula would add (2.3 × 10) kg to 50 kg, giving 73 kg (~161 lbs). The Devine formula is the most widely used of the four.

Healthy BMI Range

The World Health Organization (WHO) recommends a healthy BMI range of 18.5–25 for both males and females. Based on this range, a healthy weight can be estimated for any given height. BMI is a commonly used metric for determining IBW and is widely used in medicine as a quick indicator of potential health complications. Generally, the higher the BMI, the greater the risk of conditions such as obesity, type 2 diabetes, and heart disease.

Healthy BMI Range for Children

All the formulas above apply to adults aged 18 and older. For children and teenagers, the Centers for Disease Control and Prevention (CDC) recommends maintaining a BMI between the 5th and 85th percentile based on age and sex. Consult a paediatrician for children's weight assessment.

Limitations of IBW Calculators

All IBW formulas and methods have limitations. Because they are designed to be broadly applicable, they cannot be highly accurate for every individual. The formulas consider only height and gender — they do not account for physical disabilities, extreme body types, activity levels, or body composition (the ratio of muscle to fat). Our Ideal Weight Calculator is intended as a general guideline based on established formulas. Its results are not strict targets that a person must achieve to be considered a healthy weight.