Creatinine Clearance Calculator

How to Use

1. Enter your age in years
2. Select your biological sex (male or female)
3. Enter your weight in kilograms or pounds
4. Enter your serum creatinine level in mg/dL or μmol/L
5. Click Calculate to see your estimated creatinine clearance rate
6. Review the kidney function interpretation and stage classification

Frequently Asked Questions

What is the difference between creatinine clearance and GFR?

Creatinine clearance (CrCl) and glomerular filtration rate (GFR) both measure kidney function, but they're calculated differently. CrCl is estimated using the Cockcroft-Gault equation based on serum creatinine, age, weight, and sex. GFR is often calculated using other equations like MDRD or CKD-EPI. While they correlate closely, GFR is considered more accurate for assessing overall kidney function, while CrCl is often preferred for medication dosing adjustments.

What affects creatinine levels in the blood?

Several factors can affect serum creatinine levels: muscle mass (bodybuilders have higher levels), diet (eating meat can temporarily increase levels), age (decreases with age due to reduced muscle mass), certain medications, dehydration, kidney function, and medical conditions affecting muscle tissue. This is why the Cockcroft-Gault equation accounts for age, sex, and weight when estimating clearance.

When should I get my kidney function tested?

Regular kidney function testing is recommended if you have diabetes, high blood pressure, heart disease, family history of kidney disease, are over 60 years old, or take medications that affect the kidneys. Additionally, testing is important if you experience symptoms like fatigue, swelling, changes in urination, or unexplained nausea. Your healthcare provider can determine the appropriate testing frequency based on your individual risk factors.