Ideal Body Weight (IBW) Calculator

Ideal body weight (IBW) formulas estimate a weight associated with typical dosing or frame sizes at a given height. They were designed for adults and differ slightly by the population data they used. This calculator shows four well-known methods side by side—Devine, Hamwi, Robinson, and Miller—so you can see the range rather than a single number.

The average IBW (across formulas) gives a practical midpoint. We also compute a healthy weight range based on BMI 18.5–24.9 and estimate lean body mass (LBM) from the Boer equation using the average IBW as weight input. Use these values as orientation points, not prescriptions.

How to measure height accurately

• Stand barefoot, heels and back lightly against a wall; head neutral, eyes forward.
• Use a flat object on the crown and mark the wall; measure to the floor.
• Record to the nearest centimeter or quarter inch; if possible average two readings.

Practical tips for using your results

Think of IBW as a navigation aid, not a destination. If your current weight is above the IBW range, small, sustainable changes—like adding a 10–15 minute daily walk, prioritizing protein at meals, and sleeping 7–9 hours—tend to work better than dramatic overhauls. If you already train, pair your target with performance markers (e.g., weekly strength or pace benchmarks) so progress isn’t judged by scale weight alone. Hydration, sodium intake, and menstrual cycle phase can shift day-to-day readings; trend lines over weeks are more meaningful than single points. Finally, medical conditions, medications, and life stage can influence a healthy weight for you; use IBW alongside professional advice and how you feel in daily life—energy, recovery, and function matter.

IBW is a height-based target used in clinical contexts (e.g., drug dosing) and general guidance. It does not account for muscle mass, bone density, or fat distribution. Different formulas yield slightly different figures because they were derived from different reference groups.

BMI reflects mass relative to height and helps define broad “healthy weight” bands. However, a muscular person may exceed “normal” BMI despite low body fat.

LBM approximates the non-fat component (bone, organs, muscle). Our Boer estimate uses your average IBW as weight input to give you a ballpark body-composition anchor. Treat it as illustrative rather than diagnostic.