Creatinine Clearance Calculator
What is Creatinine Clearance Calculator
The creatinine clearance calculator estimates kidney function using the Cockcroft-Gault formula. From age, weight, serum creatinine, and sex it returns the clearance in mL/min, a value widely used to adjust drug doses. The formula is CrCl = ((140 − age) × weight) ÷ (72 × serum creatinine in mg/dL), multiplied by 0.85 for females. Both mg/dL and µmol/L units are supported.
How to use
- Enter the patient's age in years and weight in kilograms.
- Enter the serum creatinine and choose mg/dL or µmol/L.
- Select the patient's sex.
- Read the creatinine clearance in mL/min and its reference band.
When to use it
A 60-year-old man weighing 80 kg with a creatinine of 1.0 mg/dL? Enter those and you get about 89 mL/min, a mildly reduced clearance. It is the number you reach for when a drug's dosing depends on renal function.
Frequently asked questions
What is the Cockcroft-Gault formula?
CrCl (mL/min) = ((140 − age) × weight in kg) ÷ (72 × serum creatinine in mg/dL), then × 0.85 for women. For a 60-year-old, 80 kg man with creatinine 1.0 mg/dL, that is (80 × 80) ÷ 72 = about 89 mL/min.
How do I convert µmol/L to mg/dL?
Divide the µmol/L value by 88.4 to get mg/dL (1 mg/dL = 88.4 µmol/L). The calculator does this for you when you pick µmol/L, so a creatinine of 88.4 µmol/L gives the same result as 1.0 mg/dL.
Which weight should I use?
Classic Cockcroft-Gault uses actual body weight, but in obesity an adjusted or ideal body weight is often preferred to avoid overestimating clearance. Follow your local dosing guidance for the weight to enter.
Can I share this tool with my inputs pre-filled?
Yes. The URL updates automatically as you type. Copy it from the address bar or use the Share button — anyone who opens the link will see your exact inputs ready to go.
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