eGFR Calculator
Calculate estimated Glomerular Filtration Rate using the 2021 CKD-EPI creatinine equation (race-free version), the current clinical standard for kidney function assessment.
Results
What is it?
Estimated Glomerular Filtration Rate (eGFR) measures how well your kidneys filter waste from the blood, expressed as mL per minute per 1.73 m2 of body surface area. This calculator implements the 2021 CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) creatinine equation — the race-free version adopted as the clinical standard. CKD Staging by eGFR: - G1: >=90 (Normal) - G2: 60-89 (Mildly decreased) - G3a: 45-59 (Mild-moderate decrease) - G3b: 30-44 (Moderate-severe decrease) - G4: 15-29 (Severely decreased) - G5: <15 (Kidney failure)
How to use
1. Enter your serum creatinine in mg/dL (from a blood test — check your lab report). 2. Enter your age. 3. Select your biological sex. 4. The eGFR result is displayed. Compare to the CKD staging guide in the description.
Example scenario
A 55-year-old male with serum creatinine of 1.2 mg/dL: crRatio = 1.2/0.9 = 1.333 (>1). minTerm = 1. maxTerm = 1.333^-1.2 = 0.737. eGFR = 142 x 1 x 0.737 x 0.9938^55 x 1 = approximately 67 mL/min/1.73m2 — CKD Stage G2.
Pro tip
eGFR from creatinine alone can be influenced by muscle mass — athletes may have higher creatinine from muscle breakdown, leading to an underestimated eGFR. Cystatin C-based eGFR is more accurate in such cases. If your eGFR is below 60, consult your doctor. Referral to a nephrologist is typically recommended when eGFR is below 30 or declining rapidly.