eGFR (CKD-EPI 2021): Glomerular Filtration Rate Calculator
Calculate eGFR using the new 2021 CKD-EPI equation without the race variable. Accurately assess kidney function and stage Chronic Kidney Disease (CKD).
Clinical Interpretation & KDIGO Classification
The CKD-EPI equation is the globally recommended method in nephrology to reliably estimate GFR and assess baseline kidney function in adults.
Why use the new 2021 CKD-EPI Equation?
Major clinical update: This calculator uses the new 2021 CKD-EPI equation. Historically, older equations (MDRD and 2009 CKD-EPI) included a race coefficient for Black patients, based on contested assumptions about muscle mass. This approach sometimes delayed CKD diagnosis and access to transplantation.
The 2021 equation has officially removed the race variable. Endorsed by the NKF (National Kidney Foundation) and ASN, this new formula standardizes renal evaluation for all patients, offering a more equitable approach while maintaining optimal prognostic accuracy.
Clinical Implications & CKD Definition
Estimated GFR is expressed in mL/min/1.73 m² of body surface area:
- An eGFR > 90 is generally considered normal in the absence of other abnormalities.
- A persistent eGFR < 60 mL/min/1.73 m² for more than 3 months formally defines Chronic Kidney Disease (CKD).
- Persistent albuminuria (proteinuria) associated with even a normal GFR (stages G1 or G2) is also a diagnostic criterion for CKD.
Chronic Kidney Disease Stages (KDIGO)
| Stage | eGFR (mL/min/1.73 m²) | Kidney Function |
|---|---|---|
| G1 | ≥ 90 | Normal or high |
| G2 | 60 - 89 | Mildly decreased |
| G3a | 45 - 59 | Mild to moderately decreased |
| G3b | 30 - 44 | Moderate to severely decreased |
| G4 | 15 - 29 | Severely decreased |
| G5 | < 15 | Kidney failure (Dialysis/Transplant) |
References:
1. Inker LA, Eneanya ND, Coresh J, et al. New Creatinine- and Cystatin C–Based Equations to Estimate GFR without Race. N Engl J Med. 2021.
[NEJM]
2. KDIGO (Kidney Disease: Improving Global Outcomes). Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease.
[KDIGO Guidelines]
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💡 Committed to scientific accuracy, if you notice any clinical or technical discrepancy, please let us know.