eGFR Calculator (CKD-EPI 2021)

Estimated glomerular filtration rate (eGFR) estimates how much blood your kidneys filter each minute, scaled to a standard body size of 1.73 m2. A higher number means better filtering. It is reported in mL/min/1.73 m2 and is one of the main tests used to check kidney health.

It uses the CKD-EPI 2021 creatinine equation: eGFR = 142 times min(Scr/k, 1)^a times max(Scr/k, 1)^-1.200 times 0.9938^age, with an extra factor of 1.012 for females. Here Scr is serum creatinine in mg/dL, k is 0.7 for females and 0.9 for males, and a is -0.241 for females and -0.302 for males.

The 2021 CKD-EPI creatinine equation was deliberately developed without a race coefficient. The older 2009 equation included a Black race adjustment that has been removed across major guidelines, so this tool uses only creatinine, age and sex and never asks for race.

Kidney function is graded by eGFR: G1 is 90 or above (normal or high), G2 is 60 to 89 (mildly reduced), G3a is 45 to 59, G3b is 30 to 44, G4 is 15 to 29 (severely reduced) and G5 is below 15 (kidney failure). Stages G3 and lower usually need follow-up with a clinician.

No. This calculator is for general information and education only. It is not medical advice and is not a diagnosis. A single creatinine value can be affected by hydration, muscle mass and other factors, so always discuss results with a qualified clinician.

No. The eGFR calculation runs entirely in your browser. Your creatinine, age and sex are never uploaded or stored.