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NumbingDoc Calculators

BMI · Lean Body Weight · Creatinine Clearance — enter details once, get all three
⚠️ For education and learning only. No legal responsibility is accepted for use of these tools. All medical decisions rest with the treating doctor.

Patient details

📏 Body Mass Index

BMI = weight (kg) ÷ height (m)²

⚖️ Body Weights

Lean Body Weight (Boer)
Ideal Body Weight (Devine)
Adjusted Body Weight
Body Surface Area (Mosteller)

💧 Creatinine Clearance (Cockcroft-Gault)

Using actual body weight.
Using Ideal Weight (IBW)
Using Adjusted Weight
CrCl = (140 − age) × weight × (0.85 if female) ÷ (72 × Scr mg/dL)

Formulae & sources

BMI categories: WHO. Asian-Pacific cut-offs (overweight ≥23, obese ≥27.5) shown where relevant.
Lean body weight: Boer P. Am J Physiol 1984 (men 0.407·wt + 0.267·ht − 19.2; women 0.252·wt + 0.473·ht − 48.3).
Ideal body weight: Devine BJ, 1974. Adjusted body weight = IBW + 0.4 × (actual − IBW).
Body surface area: Mosteller RD. N Engl J Med 1987 — √(ht·wt/3600).
Creatinine clearance: Cockcroft DW, Gault MH. Nephron 1976;16:31-41. Creatinine SI conversion: µmol/L ÷ 88.4 = mg/dL.