Cockcroft-Gault Creatinine Clearance
Cockcroft-Gault Creatinine Clearance - a deterministic tool in Sophie Well's Clinical Math & Conversions group.
Open the Cockcroft-Gault Creatinine Clearance → Runs in your browser. No signup, no tracking.
What this is
Estimate creatinine clearance using the original Cockcroft-Gault formula (Nephron 1976): CrCl = ((140 - age) * weight in kg) / (72 * serum creatinine in mg/dL), with a 0.85 multiplier for female sex. Sophie Well returns the value in mL/min, the unit most drug labels still print.
When to use it
Use Cockcroft-Gault when a drug label or renal-dose adjustment table specifies CrCl rather than eGFR - this is still the FDA-default unit for most package inserts (vancomycin, DOACs, gabapentin, many antibiotics). For staging chronic kidney disease, use the race-free CKD-EPI 2021 eGFR instead; Cockcroft-Gault systematically over-estimates GFR in heavy patients and under-estimates in cachectic patients.
References
Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron. 1976;16(1):31-41.
Worked example: CrCl 88.89 mL/min
Sophie Well is a reference and educational tool. Not medical, legal, or financial advice. Does not replace clinician judgment, professional billing review, or legal counsel.