Calculate your ideal body weight using the Robinson formula (1983). A refined clinical IBW equation that gives slightly higher estimates than Devine for most heights.
The Robinson formula (1983) is a refined ideal body weight equation that gives slightly higher base values with lower per-inch increments compared to the Devine formula. Developed by Dr. J.D. Robinson, it was intended as an improvement based on updated population data.
The key difference: Robinson starts higher at 5'0" (52 kg for men vs. Devine's 50 kg) but adds less per inch (1.9 kg vs. 2.3 kg for men). This means Robinson gives slightly lower results at tall heights and higher at shorter heights compared to Devine.
Like all IBW formulas, Robinson provides a clinical reference weight, not a personal target. It's used in some healthcare systems as an alternative to Devine for drug dosing and nutritional assessment. Whether you are a beginner or experienced professional, this free online tool provides instant, reliable results without manual computation. By automating the calculation, you save time and reduce the risk of costly errors in your planning and decision-making process.
Robinson's formula may be more appropriate for shorter individuals where Devine tends to underestimate, and for comparing against other IBW methods. Using multiple formulas helps establish a realistic range rather than fixating on a single number. Having a precise figure at your fingertips empowers better planning and more confident decisions.
Men: IBW = 52.0 + 1.9 × (height in inches − 60) Women: IBW = 49.0 + 1.7 × (height in inches − 60) Result in kg. Healthy range: IBW ± 10%
Result: IBW: 71.0 kg (156 lbs) | Range: 63.9–78.1 kg
For a male at 5'10" (70 inches): IBW = 52.0 + 1.9 × (70 − 60) = 52.0 + 19.0 = 71.0 kg (156 lbs). This is 2 kg less than Devine's 73.0 kg because Robinson's per-inch increment (1.9 kg) is lower than Devine's (2.3 kg).
The practical difference between Robinson and Devine ranges from +2 kg (Robinson higher at 5'0") to −4 kg (Robinson lower at 6'4"). For the majority of people (5'4"–6'0"), the difference is 1–3 kg. This is well within the ±10% healthy range, so the choice of formula rarely matters for personal reference.
When comparing multiple IBW formulas, calculate the mean and range. If all four formulas agree within 3–5 kg, you have a reliable estimate. If they diverge significantly, your height may be at the extreme of the formulas' valid range, and BMI-based calculations might be more appropriate.
Robinson uses a higher base weight (52 kg vs. 50 kg for men; 49 kg vs. 45.5 kg for women) but a lower per-inch increment (1.9 vs. 2.3 for men; 1.7 vs. 2.3 for women). This means Robinson gives higher values at short heights and lower values at tall heights. The crossover point where they're equal is around 5'5" for men. Robinson was intended as an update with more conservative height adjustments.
Neither formula is definitively more accurate. Robinson may better reflect healthy weight for shorter individuals, while Devine might be more appropriate for average-to-tall heights. In clinical practice, Devine is used far more often due to historical adoption. For personal reference, comparing both formulas along with Miller and Hamwi provides a more complete picture than relying on any single formula.
Robinson published the formula in 1983, almost a decade after Devine (1974). It was intended to address some of the limitations of the Devine formula, particularly its tendency to give very low ideal weights for shorter people (under 5'4"). Robinson incorporated updated population data available in the early 1980s.
No single formula is "correct." Each was derived from different population samples and makes different assumptions. The best approach is to calculate all four (Devine, Robinson, Miller, Hamwi), take the average, and consider the range. If you're shorter than average, Robinson and Miller tend to give more reasonable values. If you're taller than average, Devine and Hamwi may be more appropriate.
Not exactly. IBW is a formula-based estimate, while "healthy weight" depends on many factors: body composition, fitness level, metabolic markers, blood pressure, and more. Someone 10% above their IBW with 15% body fat and excellent fitness markers is healthier than someone at their IBW with high visceral fat and sedentary lifestyle. Use IBW as one data point, not a goal.
No. All four IBW formulas (Devine, Robinson, Miller, Hamwi) were developed for adults aged roughly 18–65. Children use age-specific growth charts (CDC or WHO percentiles). Elderly individuals may benefit from slightly higher weights, as some research suggests lower mortality at BMI 23–28 in people over 65. For these populations, consult age-appropriate references.