Estimated kidney function from serum creatinine. Free to use.
eGFR (CKD-EPI 2021) (Estimated Glomerular Filtration Rate — CKD-EPI 2021 (race-free)) is a validated clinical instrument used to assess estimated kidney function from serum creatinine. The instrument contains 3 items.
Source / attribution: Inker LA et al. N Engl J Med. 2021;385(19):1737-1749.
The instrument's primary construct — estimated kidney function from serum creatinine — is operationalized through a fixed set of items, each with a defined response format. This standardisation is what allows eGFR (CKD-EPI 2021) scores to be compared meaningfully across clinicians, sites, and studies.
Like all screening or assessment instruments, eGFR (CKD-EPI 2021) is a structured aid — not a diagnostic test in isolation. Results should be interpreted alongside history, examination, and clinical context. Where a score crosses an actionable threshold, the next step is typically a more detailed clinical evaluation rather than a definitive diagnosis.
Answer all 3 items below to see your eGFR (CKD-EPI 2021) score and interpretation.
Each item is scored on a 2-point scale (M–F). Your score updates live as you answer.
All scoring runs in your browser. No data is sent anywhere — close the tab and the answers are gone.
eGFR (CKD-EPI 2021) uses a published formula (ckd-epi-2021) rather than simple summation. The formula and its inputs are visible in our open-source scoring engine.
Scoring notes: Race-free 2021 equation. Result is in mL/min/1.73 m². For SI creatinine (μmol/L) divide by 88.4 first.
The cutoffs below are drawn from the published validation literature. Always interpret in clinical context.
| Score range | Band | Interpretation |
|---|---|---|
| 0–14 | G5 — kidney failure | GFR < 15 mL/min/1.73 m² — kidney failure; consider RRT planning. |
| 15–29 | G4 — severely decreased | GFR 15–29; nephrology referral if not already; prepare for RRT. |
| 30–44 | G3b — moderately–severely ↓ | GFR 30–44; manage CKD complications. |
| 45–59 | G3a — mildly–moderately ↓ | GFR 45–59; assess and treat risk factors. |
| 60–89 | G2 — mildly decreased | GFR 60–89 — only abnormal if accompanied by kidney damage markers. |
| 90–200 | G1 — normal or high | GFR ≥ 90 — only abnormal if accompanied by kidney damage markers. |
eGFR (CKD-EPI 2021) uses a published formula rather than simple summation. Below is a step-by-step calculation with illustrative inputs.
| Input | Value |
|---|---|
| Creatinine | 1.0 mg/dL |
| Age | 60 |
| Sex | Female |
Score = 65 → G2 — mildly decreased
If eGFR (CKD-EPI 2021) doesn't fit your context, related instruments in nephrology include:
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|---|---|---|---|
| PHQ-9 | Severity of depression | 9 | ≈ 3 minutes |
| GAD-7 | Severity of generalized anxiety | 7 | ≈ 2 minutes |
| AUDIT | 10-item WHO screening tool for hazardous alcohol consumption and dependence. | 10 | ≈ 3 min |
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| MELD-Na | 3-month mortality in advanced liver disease; transplant prioritization | 5 | — |
eGFR (CKD-EPI 2021) (Estimated Glomerular Filtration Rate — CKD-EPI 2021 (race-free)) is a validated instrument that assesses estimated kidney function from serum creatinine.
eGFR (CKD-EPI 2021) contains 3 items.
Scores of 90–200 fall in the "G1 — normal or high" band. GFR ≥ 90 — only abnormal if accompanied by kidney damage markers.
Scores of 0–14 fall in the "G5 — kidney failure" band. GFR < 15 mL/min/1.73 m² — kidney failure; consider RRT planning.
Yes — eGFR (CKD-EPI 2021) is in the public domain and free for clinical, educational, and research use without permission.
Inker LA et al. New creatinine- and cystatin C-based equations to estimate GFR without race. N Engl J Med. 2021;385(19):1737-1749.
No. eGFR (CKD-EPI 2021) is a structured assessment aid. A score is one input alongside history, examination, and clinical context. Treatment decisions should never rest on a screening score alone.
eGFR (CKD-EPI 2021) is supported by the following peer-reviewed sources: