Creatinine Clearance (Cockcroft–Gault)
Published in 1976, this equation still governs drug dosing because weight enters it directly. Age lowers the result through (140 − age), and women are multiplied by 0.85 for muscle mass.
Your numbers
Creatinine clearance
77.8mL/min
Clearance per kg
1.11mL/min
Age
80
Formula
Creatinine clearance = (140 − Age) × Weight (kg) ÷ (72 × Creatinine (mg/dL)) × f(Sex (M1 / F0))
It overestimates in obesity; the convention there is to use ideal or adjusted body weight instead of actual.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| Creatinine (mg/dL)A muscle waste product the kidneys clear, which makes it a kidney marker. | 1 | 0.1 ~ 15 |
| AgeAge in completed years — it shifts by one depending on the birthday. | 60 | 18 ~ 100 |
| Weight (kg) (kg)The second weight you are comparing against. | 70 | 20 and up |
| Sex (M1 / F0)Where the formula splits by sex — enter 1 for male, 0 for female. | 1 | 0 ~ 1 |
Step by step
Quick reference table
Results when only Age changes and everything else stays put.
| Age | Creatinine clearance (mL/min) | Clearance per kg (mL/min) | Age |
|---|---|---|---|
| 30 | 106.9 | 1.53 | 110 |
| 45 | 92.4 | 1.32 | 95 |
| 60 | 77.8 | 1.11 | 80 |
| 90 | 48.6 | 0.69 | 50 |
| 100 | 38.9 | 0.56 | 40 |
What each result means
| Result | At default values |
|---|---|
| Creatinine clearance (mL/min)Kidney clearance including weight, used for drug dosing. | 77.8 |
| Clearance per kg (mL/min)Clearance divided by weight, which removes body-size differences. | 1.11 |
| AgeAge in completed years — it shifts by one depending on the birthday. | 80 |
Common mistakes
It overestimates in obesity; the convention there is to use ideal or adjusted body weight instead of actual.
Glossary
- Creatinine (mg/dL)
- A muscle waste product the kidneys clear, which makes it a kidney marker.
- Age
- Age in completed years — it shifts by one depending on the birthday.
- Weight (kg)
- The second weight you are comparing against.
- Sex (M1 / F0)
- Where the formula splits by sex — enter 1 for male, 0 for female.
- Creatinine clearance
- Kidney clearance including weight, used for drug dosing.
- Clearance per kg
- Clearance divided by weight, which removes body-size differences.
Frequently asked questions
Q. How is Creatinine Clearance (Cockcroft–Gault) calculated?
Creatinine clearance = (140 − Age) × Weight (kg) ÷ (72 × Creatinine (mg/dL)) × f(Sex (M1 / F0)) — Published in 1976, this equation still governs drug dosing because weight enters it directly. Age lowers the result through (140 − age), and women are multiplied by 0.85 for muscle mass.
Q. Can you walk through an example?
With Creatinine (mg/dL) 1, Age 60, Weight (kg) 70kg, Sex (M1 / F0) 1, the answer is Creatinine clearance 77.8mL/min.
Q. What do I need to enter?
Enter Creatinine (mg/dL), Age, Weight (kg), Sex (M1 / F0). The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only Age moves the answer to Age 30 → Creatinine clearance (mL/min) 106.9 and Age 100 → Creatinine clearance (mL/min) 38.9. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
It overestimates in obesity; the convention there is to use ideal or adjusted body weight instead of actual.
Related calculators
These calculators help you understand health figures; they do not replace diagnosis or prescription. See a clinician if you have symptoms.