CrCl Calculator

CrCl stands for creatinine clearance, which is an estimate of how well your kidneys filter waste from your blood, measured in milliliters per minute (mL/min). It is computed from your age, sex, weight, and serum creatinine level using the Cockcroft-Gault formula. Clinicians use CrCl to stage chronic kidney disease and adjust medication doses.

The standard Cockcroft-Gault formula is: CrCl = [(140 − age) × weight in kg × (0.85 if female)] / (72 × serum creatinine in mg/dL). If using SI units (μmol/L), the formula is adjusted accordingly. It remains the clinical gold standard for determining renal drug dosage adjustments.

For healthy adults, normal CrCl is approximately 90 to 120 mL/min for men and 80 to 110 mL/min for women. Because kidney function naturally declines with age, a lower CrCl may be expected and considered normal in older adults.

Both values estimate kidney function. CrCl (Cockcroft-Gault) reports absolute clearance in mL/min and is the primary metric for FDA-approved drug dosing. eGFR (CKD-EPI) is normalized to a standard body surface area (expressed in mL/min/1.73 m²) and is preferred by nephrologists for diagnosing and staging chronic kidney disease.

Actual body weight is typically used for most patients. However, in obese individuals, actual weight can lead to an overestimation of CrCl, so clinicians often use ideal body weight (IBW) or adjusted body weight. For underweight patients, actual body weight is preferred to avoid overestimating kidney function.