GFR Calculator
Estimate your Glomerular Filtration Rate (GFR) to assess kidney function using the CKD-EPI formula.
Input Parameters
Results
Understanding GFR & Kidney Health
eGFR (estimated Glomerular Filtration Rate) measures how well kidneys filter waste. Normal: ≥90 mL/min/1.73m². GFR 60–89: Mildly decreased. GFR 30–59: CKD Stage 3. GFR <15: Kidney failure. The CKD-EPI 2021 formula (race-free) is the current standard used by most labs.
What is the GFR Calculator?
Glomerular Filtration Rate (GFR) is widely considered the best overall index of kidney function. This tool accurately estimates how much blood passes through the tiny filters in your kidneys (glomeruli) every minute, helping you and your doctor assess the stage of any chronic kidney disease (CKD).
How It Works (Formula)
This calculator utilizes the highly recommended CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation, which relies on your serum creatinine level, age, sex, and race to estimate kidney filtration efficiency.
$$ \text{eGFR} = 141 \times \min(S_{cr}/\kappa, 1)^\alpha \times \max(S_{cr}/\kappa, 1)^{-1.209} \times 0.993^{\text{Age}} $$
The standard CKD-EPI estimating equation.
How to Use It
Obtain your serum creatinine levels from a recent blood lab report. Select your biological gender and race, enter your age, and input your creatinine value. The calculator will instantly output your GFR and identify your kidney function stage.