Creatinine Clearance Calculator

Calculate creatinine clearance (CrCl) using the Cockcroft-Gault equation for drug dosing adjustments

Clinical reference tool. Verify drug-specific dosing recommendations with pharmacist or prescribing information.

The Cockcroft-Gault equation calculates creatinine clearance, the standard method for estimating kidney function for drug dosing adjustments in renal impairment.

Cockcroft-Gault CrCl Calculator

This tool provides general health information only. Consult a qualified healthcare professional for medical advice, diagnosis, or treatment.

How to Use the Creatinine Clearance Calculator

The creatinine clearance calculator uses the Cockcroft-Gault equation — the standard formula for renal drug dosing adjustments. It requires age, sex, weight, and serum creatinine.

Drug Dosing Thresholds

Many drugs have specific dosing adjustments at CrCl thresholds: <30 mL/min (severe impairment), 30–60 mL/min (moderate), 60–90 mL/min (mild), >90 mL/min (normal). Common drugs requiring adjustment include metformin (hold if <30), dabigatran, digoxin, vancomycin, aminoglycosides, and many others.

Frequently Asked Questions

Is this creatinine clearance calculator free?

Yes, completely free with no signup required.

What is the Cockcroft-Gault equation?

CrCl (mL/min) = [(140 − age) × weight (kg)] / [72 × serum creatinine (mg/dL)]. For females, multiply by 0.85. This equation estimates kidney function and is the standard for drug dosing adjustments in renal impairment.

How is CrCl different from eGFR?

Both estimate kidney function, but they serve different purposes. eGFR (typically CKD-EPI or MDRD) is used for CKD staging and normalized to 1.73m² body surface area. CrCl (Cockcroft-Gault) uses actual body weight and is preferred for drug dosing — particularly for medications like digoxin, vancomycin, aminoglycosides, and many renally-cleared drugs.

Which weight should I use for obese patients?

For obese patients, use adjusted body weight (ABW) rather than actual weight, or ideal body weight — depending on the specific drug's prescribing information. Cockcroft-Gault uses actual body weight for non-obese patients. Consult your institution's pharmacy guidelines for obese dosing.