What this calculator does
Creatinine clearance (Cockcroft-Gault) works out estimated kidney filtration rate from age, weight and serum creatinine. Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.
The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.
The formula
FormulaCrCl = ((140 − age) × weight(kg) × sex factor) / (72 × serum creatinine), sex factor = 0.85 women / 1 men
The inputs explained
| Field | What to enter |
|---|---|
| Age (years) | A number, measured in years. Starts at 50. |
| Weight (kg) | A number, measured in kg. Starts at 75. |
| Serum creatinine (mg/dL) | A number, measured in mg/dL. Starts at 1. |
| Sex | Choose from Male, Female. |
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the answer changes with age
Every other input is held at the calculator’s starting values while age varies. Select any row to load that scenario into the calculator.
How the answer changes with age
| Age (years) | Estimated creatinine clearance | Note |
|---|---|---|
| 25 | 120 mL/min | An estimate of kidney function, not a substitute for a lab-measured GFR. |
| 37.5 | 107 mL/min | An estimate of kidney function, not a substitute for a lab-measured GFR. |
| 50 | 94 mL/min | An estimate of kidney function, not a substitute for a lab-measured GFR. |
| 75 | 68 mL/min | An estimate of kidney function, not a substitute for a lab-measured GFR. |
| 100 | 42 mL/min | An estimate of kidney function, not a substitute for a lab-measured GFR. |
| 150 | -10 mL/min | An estimate of kidney function, not a substitute for a lab-measured GFR. |