Creatinine Clearance Calculator | HealthCalculum

Calculate estimated creatinine clearance using the Cockcroft-Gault formula for kidney function assessment. Free evidence-based tool.

Important Medical Disclaimer

This calculator is an educational and clinical decision support tool. Results DO NOT replace professional medical evaluation, laboratory tests, or clinical judgment. Always consult a qualified healthcare professional for diagnosis, treatment, and clinical decisions. Calculations are based on scientifically validated formulas but may not be applicable to all patients.

Calculate Clearance

What is Creatinine Clearance?

Creatinine clearance is a measure of glomerular filtration rate (GFR), reflecting the kidneys' ability to filter waste from the blood. The Cockcroft-Gault formula is widely used to estimate clearance based on age, weight, serum creatinine, and gender. It is fundamental for assessing kidney function and adjusting medication doses.

CrCl = ((140 - age) × weight) / (72 × creatinine) × factor

How to Calculate Creatinine Clearance?

The Cockcroft-Gault formula calculates: CrCl = ((140 - age) × weight in kg) / (72 × creatinine in mg/dL). For females, multiply the result by 0.85. Normal values range from 90-120 mL/min. Lower values indicate progressive degrees of kidney impairment.

Limitations and Considerations

The Cockcroft-Gault formula may overestimate kidney function in obese individuals and underestimate in elderly patients. It should not be used in dialysis patients or those with unstable kidney function. For more accurate assessment, consider newer equations like CKD-EPI or direct GFR measurements. Always correlate with clinical picture.

Frequently Asked Questions

What is considered normal creatinine clearance?

Normal creatinine clearance values are generally between 90-120 mL/min for adults. Values below 60 mL/min indicate chronic kidney disease.

Why is the calculation different for men and women?

Women generally have less muscle mass than men, resulting in lower creatinine production. Therefore, the result is multiplied by 0.85 for women.

What is the difference between creatinine clearance and GFR?

Creatinine clearance is an estimate of the Glomerular Filtration Rate (GFR). Although related, directly measured GFR may differ from estimated clearance.

When should I repeat the test?

Frequency depends on clinical condition. In patients with chronic kidney disease, it is generally monitored every 3-6 months. Consult your nephrologist.

Scientific References

1. Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron. 1976;16(1):31-41.
2. Levey AS, Bosch JP, Lewis JB, et al. A more accurate method to estimate glomerular filtration rate from serum creatinine: a new prediction equation. Ann Intern Med. 1999;130(6):461-470.
3. National Kidney Foundation. K/DOQI clinical practice guidelines for chronic kidney disease: evaluation, classification, and stratification. Am J Kidney Dis. 2002;39(2 Suppl 1):S1-266.
4. Stevens LA, Coresh J, Greene T, Levey AS. Assessing kidney function--measured and estimated glomerular filtration rate. N Engl J Med. 2006;354(23):2473-2483.
5. Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2012 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Kidney Int Suppl. 2013;3:1-150.
6. Inker LA, Astor BC, Fox CH, et al. KDOQI US commentary on the 2012 KDIGO clinical practice guideline for the evaluation and management of CKD. Am J Kidney Dis. 2014;63(5):713-735.