Creatinine Clearance Calculator

Check your kidney health in seconds. Use a clinically trusted formula to calculate Creatinine Clearance (CrCl) and estimate your kidney filtration rate (GFR) based on your age, weight, and blood creatinine level.

Creatinine Clearance Calculator
Estimate kidney function (GFR) using the Cockcroft-Gault equation.

Provide height to view BMI and BSA (optional).

What is Creatinine Clearance?

Creatinine clearance (CrCl) is one of the most common metrics used in medicine to estimate the Glomerular Filtration Rate (GFR)—essentially, how well your kidneys are filtering waste from your blood. Creatinine is a chemical waste product generated from muscle metabolism. Healthy kidneys filter creatinine out of the blood and into the urine.

If your kidneys aren't functioning properly, the level of creatinine in your blood rises. This calculator helps translate that blood level into a flow rate (mL/min) to grade kidney health.

The Cockcroft-Gault Formula
CrCl = ((140 - Age) × Weight (kg)) / (72 × Serum Creatinine (mg/dL))

* For females, the result is multiplied by 0.85.

Why Use Our CrCl Calculator?

Medication Dosing

Many drugs require dosage adjustments based on CrCl.

Global Units Support

Auto-converts between mg/dL and µmol/L.

Instant Staging

Immediately see if results indicate mild, moderate, or severe impairment.

Free & Private

No data is stored. Calculations happen in your browser.

How to Interpret Your Results

Kidney function is often categorized into stages based on the GFR or Creatinine Clearance rate. While only a doctor can diagnose Chronic Kidney Disease (CKD), these ranges provide a general guideline.

Clearance (mL/min)Kidney Function StatusDescription
90 +NormalKidneys are functioning normally.
60 – 89Mild ImpairmentSlight loss of function; observation needed.
30 – 59Moderate ImpairmentModerate CKD; requires medical management.
15 – 29Severe ImpairmentSevere CKD; preparing for dialysis may be needed.
< 15Kidney FailureEnd Stage Renal Disease (ESRD).

How to Calculate (Step-by-Step)

Step 01

Get Your Blood Test Results

Locate your 'Serum Creatinine' level from your latest blood work.

Step 02

Enter Personal Details

Input your age, gender, and current weight.

Step 03

Select Units

Choose whether your creatinine is in mg/dL (US) or µmol/L (International).

Step 04

View Interpretation

Get your CrCl value and see which stage of kidney function it corresponds to.

Example Calculation
Male, 60 years old, 75 kg, Creatinine 1.2 mg/dL

1. Formula: ((140 - 60) × 75) / (72 × 1.2)

2. Numerator: 80 × 75 = 6,000

3. Denominator: 72 × 1.2 = 86.4

4. Result: 6,000 ÷ 86.4 = 69.4 mL/min

If this were a female, we would multiply 69.4 by 0.85 = 59.0 mL/min.

Important Medical Disclaimer

This calculator is a clinical tool intended for general information. It does not replace professional medical advice, diagnosis, or treatment. The Cockcroft-Gault formula may be less accurate for patients who are very elderly, obese, or have muscle wasting diseases. Always consult with a nephrologist or healthcare provider for interpretation of blood work.

Scientific References

  • Original Cockcroft-Gault Study (1976)

    Cockcroft DW, Gault MH. Prediction of creatinine clearance from serum creatinine. Nephron. 1976;16(1):31-41.

    → View on PubMed
  • NKF KDOQI Guidelines

    National Kidney Foundation guidelines for evaluation and management of chronic kidney disease.

    → View on Kidney.org

Frequently Asked Questions

Common questions and answers about our calculator

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