Creatinine Clearance Calculator

Calculate kidney function using the Cockcroft-Gault equation. Essential for medication dosing and assessing kidney disease progression.

Sex

Age (years)

Weight

Serum Creatinine (mg/dL)

From blood test results

Creatinine Clearance

Creatinine clearance (CrCl) estimates how well your kidneys filter waste from blood. It's measured in milliliters per minute (mL/min) and indicates kidney function. Lower values suggest decreased kidney function.

How to Use This Calculator

Select your sex (male or female)
Enter your age in years
Enter your weight in kilograms
Enter your serum creatinine from blood test results
Click Calculate to see your estimated creatinine clearance

FAQ

The Cockcroft-Gault equation is a widely used formula that estimates creatinine clearance based on age, weight, sex, and serum creatinine. It's calculated as: CrCl = [(140 - age) × weight] / (72 × serum creatinine) × [0.85 if female]. This formula is particularly useful for medication dosing adjustments.

Chronic kidney disease (CKD) is classified into 5 stages based on kidney function:

Stage 1 (≥90 mL/min): Normal or high kidney function, but with evidence of kidney damage (protein in urine, structural abnormalities). Most people have no symptoms. Focus is on slowing disease progression through blood pressure control, blood sugar management (if diabetic), and lifestyle modifications.

Stage 2 (60-89 mL/min): Mild decrease in function with signs of kidney damage. Usually no symptoms yet. Treatment focuses on managing underlying causes (diabetes, hypertension) and regular monitoring. Many people remain stable at this stage for years.

Stage 3 (30-59 mL/min): Moderate decrease in function. Some people start experiencing symptoms like fatigue, swelling, or changes in urination. Medication dosing adjustments become important. May need specialist (nephrologist) care. Stage 3 is often split into 3A (45-59) and 3B (30-44) for more precise management.

Stage 4 (15-29 mL/min): Severe decrease in function. Symptoms are more common including fatigue, nausea, swelling, and difficulty concentrating. Requires nephrology care. Planning for dialysis or transplant typically begins. Strict medication and diet management needed.

Stage 5 (<15 mL/min): Kidney failure (end-stage renal disease). Kidneys can no longer maintain body's internal environment. Most patients need dialysis or kidney transplant to survive. Without treatment, toxins accumulate causing serious complications.

Note: Progression varies greatly between individuals. Many people with early CKD never progress to kidney failure, especially with proper management.

Many medications are eliminated through the kidneys. When kidney function decreases, drugs can accumulate to toxic levels if doses aren't adjusted. CrCl helps healthcare providers determine appropriate medication doses, especially for antibiotics, chemotherapy, and medications cleared by the kidneys. This prevents both toxicity and ensures therapeutic effectiveness.

CrCl (Cockcroft-Gault) and eGFR (estimated Glomerular Filtration Rate) are both estimates of kidney function but use different formulas. CrCl uses actual body weight and is preferred for medication dosing. eGFR (MDRD or CKD-EPI equations) is standardized to body surface area and preferred for diagnosing and staging chronic kidney disease. Your doctor may use both depending on the clinical situation.

Creatinine levels can be affected by muscle mass (higher in muscular individuals), recent meat consumption, certain medications, dehydration, intense exercise, and various medical conditions. This is why a single creatinine measurement should be interpreted by your healthcare provider in context of your complete medical history and physical examination.

Calculator Limitations

Estimation only: This is an estimate, not a direct measurement of kidney function
Body composition: Less accurate in obesity, extreme muscle mass, or amputees
Elderly patients: May overestimate clearance in very elderly patients
Not for children: Not validated for patients under 18 years old
Acute conditions: Less reliable during acute kidney injury or rapidly changing kidney function

Medical Disclaimer: This calculator is for educational purposes only and should not replace professional medical advice. Creatinine clearance is an estimate and should be interpreted by a healthcare provider in context of your complete medical history. Always consult your doctor for proper diagnosis and management of kidney disease.

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