Creatinine Clearance Calculator
Estimate kidney filtration using either the Cockcroft-Gault equation or a 24-hour urine collection method.
What is creatinine clearance?
Creatinine clearance (often called clearance creatinina) is an estimate of how well your kidneys filter waste from blood. Creatinine is a byproduct of muscle metabolism, and healthy kidneys remove it efficiently through urine. Lower clearance values can indicate reduced kidney function.
How this clearance creatinina calculator works
This page gives you two practical ways to calculate creatinine clearance:
- Cockcroft-Gault estimate: Uses age, sex, weight, and serum creatinine.
- 24-hour urine method: Uses measured urine creatinine, blood creatinine, urine volume, and collection time.
The Cockcroft-Gault method is fast and commonly used for medication dosing. The 24-hour urine method can be useful when direct measurement is preferred.
Interpretation guide (general reference)
| Creatinine Clearance (mL/min) | General Interpretation |
|---|---|
| ≥ 90 | Usually within normal adult range |
| 60 - 89 | Mild decrease in kidney function |
| 30 - 59 | Moderate decrease |
| 15 - 29 | Severe decrease |
| < 15 | Kidney failure range (urgent clinical assessment needed) |
Step-by-step usage
1) Choose your method
Select either Cockcroft-Gault or 24-hour urine collection from the dropdown at the top of the calculator.
2) Enter accurate lab values
Always copy your lab values exactly as shown on your report, including units. If you use the Cockcroft-Gault calculator and your serum creatinine is in µmol/L, the tool automatically converts it to mg/dL.
3) Review the result in context
A single value is helpful, but trends over time are often more important. Compare current and previous measurements, and discuss any decline with your clinician.
Important limitations
- Equations may be less accurate in pregnancy, extreme body size, edema, amputation, or very low/high muscle mass.
- Creatinine can lag behind sudden changes in kidney injury.
- Drug dosing decisions may require additional clinical judgment and other kidney markers (such as eGFR or cystatin C).
- 24-hour urine tests can be inaccurate if collection is incomplete.
FAQ
Is creatinine clearance the same as eGFR?
Not exactly. They are related but calculated differently. eGFR is usually normalized to body surface area and often reported automatically by labs. Creatinine clearance is frequently used for medication dosing.
Which result should I trust more?
It depends on the clinical situation. Cockcroft-Gault is convenient and common in prescribing. A properly collected 24-hour urine test can provide a direct measured estimate.
Can hydration affect creatinine values?
Yes. Hydration, muscle mass, diet, and recent exercise can influence creatinine measurements. Follow lab preparation guidance whenever possible.
Should I self-diagnose kidney disease with this tool?
No. Use this calculator for education and discussion. Diagnosis and treatment should always come from a licensed healthcare professional.
Medical disclaimer
This calculator is for informational purposes only and does not replace medical advice, diagnosis, or treatment. If you have abnormal kidney-related symptoms, chronic conditions, or medication concerns, consult your doctor promptly.