Enter patient data
This page is designed for adult calculations. The result is displayed above this form after submission.
Example data table
| Case | Sex | Age | Weight (kg) | Height (cm) | SCr (mg/dL) | Weight basis | CrCl (mL/min) |
|---|---|---|---|---|---|---|---|
| Example A | Male | 45 | 78 | 178 | 1.0 | Actual | 102.92 |
| Example B | Female | 68 | 62 | 160 | 1.3 | Actual | 40.54 |
| Example C | Male | 74 | 92 | 172 | 2.1 | Actual | 40.16 |
Formula used
The Cockcroft–Gault equation estimates creatinine clearance in mL/min using age, sex, weight, and serum creatinine.
- Male: CrCl = ((140 − age) × weight in kg) ÷ (72 × serum creatinine in mg/dL)
- Female: CrCl = Male result × 0.85
- Unit conversion: serum creatinine in µmol/L is divided by 88.4
- Ideal body weight: Male = 50 + 2.3 × inches over 60; Female = 45.5 + 2.3 × inches over 60
- Adjusted body weight: AdjBW = IBW + 0.4 × (Actual BW − IBW)
- BSA: Mosteller = √((height cm × weight kg) ÷ 3600)
- Normalized value: CrCl × (1.73 ÷ BSA)
Auto mode is a practical calculator rule. It uses adjusted body weight when actual body weight is above 120% of ideal body weight.
How to use this calculator
- Enter the patient’s age, sex, serum creatinine, actual weight, and height.
- Select the creatinine unit that matches the laboratory report.
- Choose a weight method or leave it on Auto.
- Set the number of decimal places for display.
- Click Calculate Clearance.
- Review the creatinine clearance, normalized value, weight details, and renal function band.
- Use the chart for quick visual review.
- Download the result as CSV or PDF when needed.
FAQs
1. What does this calculator estimate?
It estimates creatinine clearance using the Cockcroft–Gault method. The result helps with medication review, renal dosing checks, and quick bedside calculations for adults.
2. Is creatinine clearance the same as eGFR?
No. They are related but not identical. Cockcroft–Gault estimates creatinine clearance in mL/min, while eGFR formulas usually report values normalized to 1.73 m².
3. Why does the calculator ask for height?
Height is used to estimate ideal body weight, adjusted body weight, BMI, and body surface area. These values support more flexible interpretation of the result.
4. What does Auto weight selection do?
Auto mode uses actual body weight unless the patient’s actual weight exceeds 120% of ideal body weight. In that situation, it switches to adjusted body weight.
5. Can I use µmol/L laboratory values?
Yes. Choose µmol/L in the unit field. The calculator converts the value to mg/dL before applying the Cockcroft–Gault equation.
6. Why is there a separate normalized result?
The normalized value adjusts the calculated clearance to a standard body surface area of 1.73 m². It is useful for side-by-side comparison with other renal metrics.
7. When should this result be interpreted carefully?
Use extra caution with unstable creatinine, acute kidney injury, pregnancy, dialysis, amputation, edema, or very unusual body composition. Clinical review remains essential.
8. Can this replace clinical judgment?
No. It is a structured support tool. Medication decisions still require the patient’s diagnosis, laboratory trend, fluid status, dosing objective, and official prescribing guidance.