Ideal Body Weight Calculator
Ideal body weight (IBW) is an estimate of a healthy weight for a given height and sex, often used in medicine for dosing and nutrition. This calculator uses the Devine and Robinson formulas, shows a healthy weight range, and lets you compare with your current weight.
What Is the Ideal Body Weight Calculator?
The ideal body weight calculator estimates a healthy weight for your height and sex using the Devine and Robinson formulas. It shows a single IBW value, a ±10% healthy range, and lets you compare with your current weight. Ideal body weight was originally used in medicine for dosing; it is now also used as one reference for weight goals. The calculator supports metric and imperial units.
How Does the Ideal Body Weight Calculator Work?
You enter your height (cm or feet and inches) and sex. The calculator converts to metric and applies the Devine formula (and optionally the Robinson formula) to get ideal body weight in kg. A ±10% range around that number is shown as a healthy weight range. If you enter your current weight, you can see how it compares to the range.
Why Use This Ideal Body Weight Calculator?
An ideal body weight calculator gives you a height-based reference for a healthy weight. It is useful for context when setting goals or when a clinician uses IBW for dosing. Use it alongside our BMI calculator and body fat calculator for a fuller picture of weight and composition.
Who Should Use This Tool?
Anyone curious about a height-based healthy weight range can use this ideal body weight calculator. It suits adults who want one number to compare with their current weight. Athletes and very muscular people may sit above IBW and still be healthy; the calculator is a guide, not a diagnosis. For calorie or nutrition targets, use our calorie calculator or TDEE calculator.
What is Ideal Body Weight?
Ideal body weight (IBW) is a height- and sex-based estimate of a "healthy" weight. It was originally developed for drug dosing and clinical use, not as a personal goal. IBW formulas do not account for age, muscle mass, bone structure, or body fat, so they are rough guides. Many people are healthy above or below their calculated IBW.
How is IBW calculated?
IBW is calculated from height and sex using equations that were derived from population data. The two most common are the Devine formula (1974) and the Robinson formula (1983). Both give a single number in kilograms; a ±10% range around that number is often used as a "healthy weight range" for that height.
Devine formula explanation
The Devine formula is the most widely used in medical contexts. For men, ideal body weight (kg) = 50 + 0.9 × (height in cm − 152). For women, IBW (kg) = 45.5 + 0.9 × (height in cm − 152). So for each centimeter above 152 cm, the ideal weight increases by 0.9 kg, with a different starting point for each sex. Heights below 152 cm are handled by the same formula (the result is lower).
Is IBW accurate?
IBW is a simple estimate, not a precise measure of health. It was designed for clinical use (e.g. drug dosing), not for judging whether an individual is "too heavy" or "too light." It ignores body composition, so a very muscular person can be "over" IBW and healthy, while someone with low muscle mass might be "at" IBW but carry more body fat than is ideal. Use IBW as one reference, alongside BMI, how you feel, and advice from your doctor.
Limitations of IBW
IBW does not consider age, ethnicity, muscle mass, bone density, or body fat distribution. It assumes a "reference" body shape and composition that does not apply to everyone. Athletes, older adults, and people with different body types may find that their healthy weight is outside the calculated range. For personalized targets, combine this tool with a BMI calculator, a calorie calculator, or guidance from a healthcare provider.