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eGFR Calculator
CKD-EPI 2021 race-free eGFR from creatinine, age and sex, with the KDIGO stage — a screening estimate. Accurate, instant and free — for United States.
What these mean:
What these mean:
An eGFR of 59 mL/min/1.73m² is CKD stage G3a — Mild–moderate decrease. Stage: G3a (Mild–moderate decrease).
Rates as of 2026eGFR
59 mL/min/1.73m²
CKD stage: G3a — Mild–moderate decrease
This uses the CKD-EPI 2021 race-free equation
A single eGFR is not a CKD diagnosis
How we calculate this
Reviewed by Reckonist Editorial · Last reviewed July 2026. Figures follow the methods and sources set out in our editorial standards.
Uses the CKD-EPI 2021 race-free equation (CKD-EPI 2021 (race-free)); KDIGO G1–G5 stages. General health information, not medical advice — consult a clinician.
CKD-EPI 2021 (race-free) · KDIGO stages · NKF/NIDDK 2026
Tracking blood sugar too? See the A1C Calculator.
How eGFR is calculated (CKD-EPI 2021)
Estimated glomerular filtration rate (eGFR) approximates how well your kidneys filter blood, in mL/min/1.73 m². This tool uses the CKD-EPI 2021 creatinine equation — the race-free NKF/ASN standard — from your serum creatinine, age and sex, then maps the result to a KDIGO stage (G1–G5).
CKD-EPI 2021 (race-free)
creatinine, age, sex → eGFR
eGFR = 142 × min(Scr/κ,1)^α × max(Scr/κ,1)^−1.200 × 0.9938^Age × (1.012 if female)
Scr = serum creatinine (mg/dL); κ = 0.7 (female) / 0.9 (male); α = −0.241 (female) / −0.302 (male). No race term — that is the point.
KDIGO staging
eGFR → CKD stage
G1 ≥90 · G2 60–89 · G3a 45–59 · G3b 30–44 · G4 15–29 · G5 <15
G1/G2 count as CKD only with kidney-damage markers (e.g. albuminuria).
- 1Ratio: Scr/κ = 1.1 / 0.7 = 1.571 (female κ = 0.7), so min(ratio,1) = 1 and max(ratio,1) = 1.571.
- 2Combine: 142 × 1^−0.241 × 1.571^−1.200 × 0.9938^55 × 1.012 ≈ 59 mL/min/1.73m² → stage G3a.
Race-free is the current standard — the old equations are deprecated
Until 2021 the CKD-EPI equation applied a separate multiplier for Black patients, raising the reported eGFR and risking delayed diagnosis. An NKF-ASN task force removed the race coefficient and re-derived the equation. This calculator implements only the CKD-EPI 2021 race-free version.
No race input — by design
KDIGO CKD stages G1–G5
eGFR buckets into six KDIGO stages: G1 (≥90) normal or high, G2 (60–89) mildly decreased, G3a (45–59) mild–moderate, G3b (30–44) moderate–severe, G4 (15–29) severely decreased, and G5 (<15)kidney failure — all in mL/min/1.73 m². Stages G1 and G2 are only CKD when a kidney-damage marker such as albuminuria is also present, which is why full staging pairs eGFR with the urine albumin-to-creatinine ratio.
Units and the diagnosis boundary
Serum creatinine is reported in mg/dL (US) or µmol/L (international); they convert with mg/dL = µmol/L ÷ 88.42, and this tool labels every value. Crucially, a single eGFR is not a diagnosis: KDIGO requires the abnormality to persist for at least 3 months plus assessment of albuminuria. eGFR also drifts with hydration, acute illness and muscle mass — treat one number as a prompt to talk to a clinician, not a verdict.
A single eGFR is not a CKD diagnosis
Frequently asked questions
It uses the CKD-EPI 2021 creatinine equation, which is race-free — the current standard recommended by the National Kidney Foundation and the American Society of Nephrology since 2021, and used by US labs. It deliberately has no race input. The older 2009 race-adjusted CKD-EPI and the MDRD equation are deprecated and are not used here.
The 2009 CKD-EPI equation applied a separate multiplier for Black patients, which produced a higher eGFR and could delay diagnosis or referral. In 2021 an NKF-ASN task force removed the race coefficient and re-derived the equation. Many online calculators and AI answers still show the old race-adjusted or MDRD result, so getting the current, race-free number matters.
KDIGO stages eGFR as: G1 is 90 or higher (normal or high), G2 is 60–89 (mildly decreased), G3a is 45–59 (mild–moderate decrease), G3b is 30–44 (moderate–severe decrease), G4 is 15–29 (severely decreased), and G5 is below 15 (kidney failure). G1 and G2 are only considered CKD when kidney-damage markers such as albuminuria are also present.
No. A KDIGO diagnosis of CKD requires the abnormality to persist for at least 3 months, and staging also uses albuminuria (the ACR). A single eGFR is a snapshot — it can dip transiently with dehydration, illness or acute kidney injury. Discuss any result with a clinician who can repeat the test and add a urine albumin measurement.
Choose µmol/L as the unit and enter the value. The calculator converts to mg/dL (mg/dL = µmol/L ÷ 88.42) because CKD-EPI 2021 is defined in mg/dL. For example, 97.3 µmol/L is about 1.1 mg/dL. US reports use mg/dL; most other countries use µmol/L.
Creatinine-based eGFR is less accurate at extremes of muscle mass (bodybuilders, amputees, frailty), in pregnancy, in acute kidney injury when creatinine is changing rapidly, and with high-protein or creatine supplement intake. In those cases a clinician may add a cystatin-C-based eGFR or other testing.
Yes — it is completely free with no sign-up, and every calculation runs entirely in your browser. Nothing you enter is sent to a server or stored. It is general health information for education, not medical advice.
Method, standards & references
Methodology: eGFR uses the CKD-EPI 2021 creatinine equation (race-free): 142 × min(Scr/κ,1)^α × max(Scr/κ,1)^−1.200 × 0.9938^Age × 1.012 (if female), with κ = 0.7/0.9 and α = −0.241/−0.302 (female/male); Scr in mg/dL (µmol/L ÷ 88.42). KDIGO stages: G1 ≥90, G2 60–89, G3a 45–59, G3b 30–44, G4 15–29, G5 <15 mL/min/1.73 m². The deprecated 2009 race-adjusted CKD-EPI and MDRD equations are not used. Constants are held in versioned config (CKD-EPI 2021 (race-free)); all calculations run client-side and nothing is stored. Reference method as of 2026. A single eGFR is a screening estimate, not a diagnosis.
Cross-links
How we calculate this
Reviewed by Reckonist Editorial · Last reviewed July 2026. Figures follow the methods and sources set out in our editorial standards.
This tool uses the CKD-EPI 2021 race-free equation (CKD-EPI 2021 (race-free)) and KDIGO G1–G5 stages. It is general health information for education, not medical advice, and a single eGFR is not a diagnosis of chronic kidney disease — KDIGO requires persistence of ≥3 months plus albuminuria. eGFR is less reliable at extremes of muscle mass, in amputees, pregnancy or acute kidney injury — always confirm with a clinician.
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