Glomerular Filtration Rate (GFR) Calculator
This calculator estimates GFR based on the CKD-EPI 2021 equation. It is intended for use by healthcare professionals.
Your eGFR Result
Enter patient data above to calculate the estimated Glomerular Filtration Rate.
What is Glomerular Filtration Rate (GFR)?
Glomerular Filtration Rate (GFR) is the best overall index of kidney function. The kidneys contain millions of tiny filtering units called glomeruli, which remove waste products from the blood while preventing the loss of important substances like proteins and red blood cells. GFR represents the total volume of fluid filtered by these glomeruli per unit of time.
How is eGFR Calculated?
A direct measurement of GFR is complex, so it is usually estimated using a mathematical formula. This is known as the estimated GFR, or eGFR. This calculator uses the **CKD-EPI 2021 Equation**, which is the most current and widely accepted formula. It provides an estimate based on a patient's serum creatinine level, age, gender, and race.
The Stages of Chronic Kidney Disease (CKD)
Your eGFR result is used to determine the stage of Chronic Kidney Disease. Note that a diagnosis of Stage 1 or 2 CKD also requires other evidence of kidney damage (like proteinuria).
| Stage | eGFR (mL/min/1.73m²) | Description |
|---|---|---|
| Stage 1 | ≥ 90 | Normal or high function, but with signs of kidney damage. |
| Stage 2 | 60-89 | Mildly decreased function, with other signs of kidney damage. |
| Stage 3a | 45-59 | Mild to moderately decreased function. |
| Stage 3b | 30-44 | Moderately to severely decreased function. |
| Stage 4 | 15-29 | Severely decreased function. |
| Stage 5 | < 15 | Kidney failure. |
Overall health status, such as being in a healthy weight range determined by a BMI calculator, can positively impact kidney health and slow the progression of kidney disease.
DISCLAIMER: This tool is intended for educational purposes only and is not a substitute for professional medical judgment. It is designed to be used by qualified healthcare professionals. Do not use this calculator to make a self-diagnosis. If you are a patient, discuss your eGFR result with your doctor, who can interpret it in the context of your overall health.