Ideal Weight Calculator - Healthy Range
Calculate your ideal body weight using Robinson, Miller, Devine, and BMI-based formulas. Accounts for height, age, frame size, and gender for accurate
Formula
IBW = 50 + 2.3 × (height(in) - 60) for men
The Devine formula calculates ideal weight based on height. Different formulas exist, providing a range rather than a single target.
Worked Examples
Example 1: Average Male
Problem:Calculate ideal weight for male, 180cm tall.
Solution:Height in inches = 180cm / 2.54 = 70.9 inches\n\nDevine Formula:\nIBW = 50 + 2.3 × (70.9 - 60)\nIBW = 50 + 2.3 × 10.9 = 75.1 kg\n\nBMI Range (18.5-24.9):\nMin: 18.5 × (1.80)² = 60.0 kg\nMax: 24.9 × (1.80)² = 80.6 kg\n\nHealthy range: 60-81 kg\nFormula average: ~75 kg
Result:75 kg ideal, 60-81 kg healthy range
Example 2: Female Example
Problem:Calculate for female, 5'4\" (64 inches).
Solution:Height = 64 inches = 162.6 cm\n\nDevine Formula:\nIBW = 45.5 + 2.3 × (64 - 60)\nIBW = 45.5 + 2.3 × 4 = 54.7 kg = 121 lbs\n\nRobinson Formula:\nIBW = 49 + 1.7 × 4 = 55.8 kg = 123 lbs\n\nBMI Range:\n18.5 × (1.626)² = 48.9 kg (108 lbs)\n24.9 × (1.626)² = 65.8 kg (145 lbs)\n\nHealthy range: 108-145 lbs
Result:55 kg (121 lbs) ideal, 109-145 lbs healthy
Example 3: Using for Goal Setting
Problem:Person is 170cm, currently 95kg, wants a target weight.
Solution:Height = 170cm\n\nIdeal weight formulas average: ~68 kg\nBMI healthy range: 53.4-71.8 kg\n\nCurrent: 95 kg\nIdeal target: 68 kg\nDifference: 27 kg\n\nAt 0.5kg/week: 54 weeks\nAt 0.75kg/week: 36 weeks\n\nRealistic initial target: 80 kg (in 6 months)\nThen reassess for final target.
Result:Set intermediate goal of 80 kg first
Frequently Asked Questions
What is ideal body weight?
Ideal body weight (IBW) is an estimated healthy weight based on height and sex. Multiple formulas exist (Devine, Robinson, Miller, Hamwi), each giving slightly different results. These are guidelines, not strict targets. Healthy weight exists within a range, not a single number.
Which ideal weight formula is best?
No single formula is definitively 'best.' Devine is most commonly used in medicine. Robinson and Miller are newer refinements. Hamwi is simpler. For most people, the average of multiple formulas is reasonable. BMI-based ranges (18.5-24.9) provide a healthy weight range rather than a single target.
How is ideal weight used in medicine?
IBW is used for: drug dosing (especially when actual weight is very high or low), ventilator settings, nutritional planning, and as a reference point in clinical assessments. For obesity, adjusted body weight (ABW) may be used rather than actual or ideal weight.
Does ideal weight account for body type?
No. These formulas only use height and sex. They don't account for: bone structure, muscle mass, ethnicity, age, or frame size. A muscular athlete may exceed IBW while being very healthy. Use IBW as one reference point among many health indicators.