Creatinine Clearance Calculator
Estimate creatinine clearance with Cockcroft-Gault, using actual, ideal or adjusted body weight.
Choose a sex, then enter the creatinine result, the age, height and weight to see the result.
Not indexed to body surface, unlike the eGFR Calculator.
Estimates creatinine clearance (CrCl) in mL/min from serum creatinine, age, sex and weight with the Cockcroft-Gault equation, the formula behind many drug-dosing studies. It works out the clearance three ways — with actual, ideal and adjusted body weight — and marks the weight a 2012 study found least biased for the person's BMI. Every calculation runs in your browser.
How it works
Creatinine in µmol/L is converted to mg/dL by dividing by 88.4. Ideal body weight is Devine's: 50 kg for men and 45.5 kg for women at 5 ft, plus 2.3 kg for each inch above. Below 5 ft (152.4 cm) Devine gives no weight, so only actual weight is used. Adjusted weight adds 40% of the weight above ideal.
Winter and colleagues (2012) compared the equation against measured 24-hour clearance in 3,678 patients: actual weight was unbiased in underweight patients, ideal weight in patients of normal weight, and adjusted weight the least biased and most accurate above that. MDCalc's review bands this by BMI — below 18.5, 18.5 to 24.9, and 25 or more — and the tool marks the weight for the BMI entered. Winter also found that rounding a low creatinine up did not improve accuracy, so the tool uses the value as entered.
The result is in mL/min for the person, not scaled to 1.73 m² of body surface as eGFR is, and it is shown to the nearest whole number.
CrCl (mL/min) = (140 − age) × weight (kg) ÷ (72 × creatinine mg/dL) × 0.85 [if female]
Ideal weight (kg) = 50 [men] or 45.5 [women] + 2.3 × (height in inches − 60)
Adjusted weight = ideal + 0.4 × (actual − ideal)
Examples
Man, 70, 175 cm, 95 kg, creatinine 1.3 mg/dL
actual body weight (95.0 kg): 71 mL/min; ideal body weight (devine) (70.5 kg): 53 mL/min; adjusted body weight (80.3 kg): 60 mL/min. At a BMI of 31.0 the suggested weight is adjusted body weight.
Woman, 82, 160 cm, 52 kg, creatinine 88 µmol/L
actual body weight (52.0 kg): 36 mL/min; ideal body weight (devine) (52.4 kg): 36 mL/min; adjusted body weight (52.2 kg): 36 mL/min. At a BMI of 20.3 the suggested weight is ideal body weight (devine).
Rules and sources
The equation is Cockcroft and Gault's 1976 formula, with clearance 15% lower in women. The weight bands follow Winter et al. (2012) as MDCalc's review applies them, and the Devine formula is as Pai and Paloucek trace it.
Sources
- Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine (Nephron 1976;16:31–41) — Nephron
- KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease (Kidney Int 2024;105(4S):S117–S314) — KDIGO
- Winter MA et al. Impact of various body weights and serum creatinine concentrations on the bias and accuracy of the Cockcroft-Gault equation (Pharmacotherapy 2012;32:604–612) — PubMed
- Szczech L. Updated review of creatinine clearance (Cockcroft-Gault equation) (MDCalc Journal 2025) — MDCalc
- Pai MP, Paloucek FP. The origin of the “ideal” body weight equations (Ann Pharmacother 2000;34:1066–1069) — PubMed
Reviewed
Frequently asked questions
See also
- eGFR Calculator — eGFR by CKD-EPI 2021 and the CKD stage.
- Ideal Weight Calculator — Devine and the other ideal weight formulas.