Estimated GFR (CKD-EPI 2021)
The CKD-EPI 2021 equation is the recommended race-free formula for eGFR estimation. Used to diagnose and stage chronic kidney disease (CKD) and to guide drug dosing, contrast decisions, and specialist referral.
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eGFR (mL/min/1.73 m²)
CKD-EPI 2021 Formula:
eGFR = 142 × min(Scr/κ, 1)α × max(Scr/κ, 1)−1.200 × 0.9938Age × (1.012 if female)
Where: κ = 0.7 (female) or 0.9 (male) · α = −0.241 (female) or −0.302 (male)
Endorsed by: NKF-ASN 2021 Task Force — eliminates race as a variable for more equitable eGFR reporting.
eGFR = 142 × min(Scr/κ, 1)α × max(Scr/κ, 1)−1.200 × 0.9938Age × (1.012 if female)
Where: κ = 0.7 (female) or 0.9 (male) · α = −0.241 (female) or −0.302 (male)
Endorsed by: NKF-ASN 2021 Task Force — eliminates race as a variable for more equitable eGFR reporting.
CKD Staging Reference
KDIGO 2024 G-staging by eGFR (mL/min/1.73 m²). Full CKD staging also includes urine albumin-to-creatinine ratio (A-staging).
| Stage | eGFR Range | Description | Key Actions |
|---|---|---|---|
| G1 | ≥ 90 | Normal or high | Treat risk factors; confirm with uACR |
| G2 | 60–89 | Mildly decreased | Monitor annually; control BP, glucose |
| G3a | 45–59 | Mild–moderately decreased | Nephrology consult; SGLT2i if DM |
| G3b | 30–44 | Moderately–severely decreased | Nephrology referral; adjust medications |
| G4 | 15–29 | Severely decreased | Prepare for RRT; transplant evaluation |
| G5 | < 15 | Kidney failure | Dialysis or transplant |
Endocrine relevance: eGFR affects dosing of metformin (hold if eGFR <30), SGLT2 inhibitors (reduced efficacy <45), GLP-1 agonists, insulin clearance, and contrast media safety for imaging. Hypothyroidism and primary hyperaldosteronism can affect creatinine independently.
In the Houston area?
Have questions about kidney function with diabetes? See an endocrinologist.
Diabetes and kidney protection (SGLT2 inhibitors, Kerendia), at Endocrine & Diabetes Plus in Sugar Land and Memorial City. New patients are usually seen within 2 weeks; the earliest openings are with Dr. Chhavi Chadha. Telehealth follow-ups for patients anywhere in Texas.
Outside Texas? Share this result with your own doctor. This tool is for information only.
⚕️ Clinical note: eGFR is an estimate. Results may be less accurate in extremes of body size, muscle mass, diet (high meat intake), or acute illness. For precise assessment, 24-hour urine creatinine clearance or cystatin C-based eGFR may be preferred. CKD diagnosis requires two measurements ≥90 days apart. Based on CKD-EPI 2021 (Inker LA et al., NEJM 2021;385:1737–1749).