Creatinine clearance calculator (Cockcroft-Gault)
This tool estimates creatinine clearance in mL per minute, the value many drug labels use for kidney dose adjustment.
Loading the tool…
Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter sex, age, weight, serum creatinine and creatinine unit.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
CrCl = (140 - age) × weight (kg) ÷ (72 × Scr in mg/dL), multiplied by 0.85 for women. Creatinine in µmol/L is first divided by 88.4.
Example
Inputs: Sex = Male, Age = 60 years, Weight = 72 kg, Serum creatinine = 1, Creatinine unit = mg/dL. Result: Creatinine clearance: 80 mL/min; Creatinine in mg/dL: 1.
Limits and caveats
- It uses the weight you enter; in marked obesity a pharmacist may use ideal or adjusted body weight instead.
- The result is not indexed to body surface area and does not fit an unstable creatinine.
- An educational estimate that does not replace assessment by a doctor or pharmacist.
Questions about this tool
When is Cockcroft-Gault used instead of eGFR?
Many drug labels set their kidney doses with it, so pharmacists use it for dose adjustment, while eGFR is used to stage kidney disease.
Why multiply by 0.85 for women?
Women have less muscle mass on average and make less creatinine. The factor comes from the original 1976 study.
What unit is the result in?
mL per minute, not indexed to 1.73 m² as eGFR is.