Creatinine Clearance Calculator
Estimate creatinine clearance with the Cockcroft-Gault equation, often used to adjust medicine doses.
About the Creatinine Clearance Calculator
The Cockcroft-Gault equation (1976) estimates how fast the kidneys clear creatinine. It isn't adjusted for body surface area, which is why many drug-dosing guides still use it. Which weight to use (actual, ideal or adjusted) depends on the drug and the patient's build.
The formula
CrCl = ((140 − age) × weight(kg)) ÷ (72 × Scr(mg/dL)) × 0.85 if female
Worked example
Example: Creatinine clearance (Cockcroft-Gault) = 70 mL/min
- Inputs: Units: lb / ft; Sex: Male; Age: 66 years; Weight: 180 lb; Creatinine unit: mg/dL; Serum creatinine: 1.2.
- Formula: CrCl = ((140 − age) × weight(kg)) ÷ (72 × Scr(mg/dL)) × 0.85 if female
- Cockcroft-Gault ((140 − 66) × 81.6) ÷ (72 × 1.2) = 69.9 mL/min
- Result: Creatinine clearance (Cockcroft-Gault) = 70 mL/min
Things to keep in mind
- For prescribing decisions follow the drug label and a pharmacist's advice.
Questions people ask
How is this different from eGFR?
eGFR is standardised to body surface area and used to stage kidney disease; CrCl is in mL/min for the individual and used for dosing.
Which weight should I use?
Actual weight here; for people with obesity many protocols use adjusted body weight.