Why no race coefficient?

The race adjustment in the 2009 CKD-EPI equation introduced bias; NKF/ASN concluded a race-free equation is more equitable and equally accurate (Powe et al., NEJM 2021).

Inker 2021 also publishes eGFRcys and eGFRcr-cys equations using cystatin C (more accurate, less affected by muscle mass). Use when creatinine is unreliable (frail elderly, amputees).

When does eGFR underestimate?

High muscle mass (bodybuilders), recent meat ingestion (acute creatinine bump), creatinine-secreting drugs (trimethoprim, cimetidine). Use cystatin C or 24-hr creatinine clearance.

G1 ≥90, G2 60-89, G3a 45-59, G3b 30-44, G4 15-29, G5 <15 mL/min/1.73 m². CKD requires reduced eGFR + abnormality (proteinuria, imaging, biopsy) sustained ≥3 months.

Is this medical advice?

No. Educational. CKD diagnosis requires clinical correlation, urine albumin, and confirmation.

eGFR (CKD-EPI 2021, race-free) Calculator

eGFR from creatinine, age, sex per CKD-EPI 2021 (Inker et al., NEJM). Race-free formula adopted by NKF/ASN.

Result

eGFR

91.7 mL/min/1.73 m²

G1 — Normal/high. Male, age 50, Scr 1 mg/dL.

Creatinine (mg/dL)1
Age50
SexMale
κ (kappa)0.90
α (alpha)-0.302
eGFR91.7 mL/min/1.73 m²
KDIGO stageG1 — Normal/high

G1 — Normal/high

0 mL/min/1.73 m²91.6914786098333 mL/min/1.73 m²120 mL/min/1.73 m²

KDIGO 2024 GFR categories. Persistent ≥3 mo for CKD diagnosis.

Source: Inker AS et al., "New Creatinine- and Cystatin C-Based Equations to Estimate GFR Without Race." NEJM 2021;385:1737–49 (CKD-EPI 2021).

Not medical advice — eGFR is an estimate; confirm CKD with a repeat measurement ≥3 months later plus albuminuria. Not valid in acute kidney injury, pregnancy, extreme muscle mass (amputees, body-builders), or rapidly changing creatinine.

Step-by-step

κ = 0.9 (male); α = -0.302.
min(Scr/κ, 1)^α = min(1.1111, 1)^-0.302 = 1.0000.
max(Scr/κ, 1)^(-1.200) = max(1.1111, 1)^(-1.2) = 0.8812.
0.9938^age = 0.9938^50 = 0.7327.
eGFR = 142 × 1.0000 × 0.8812 × 0.7327 = 91.7.

How to use this calculator

Enter serum creatinine (mg/dL; convert from µmol/L by × 0.0113).
Enter age and sex.
Read eGFR + KDIGO stage. Confirm diagnosis with second measurement.

About this calculator

CKD-EPI 2021 eGFR equation (Inker AS et al., "New Creatinine- and Cystatin C-Based Equations to Estimate GFR Without Race." NEJM 2021;385:1737-49). Race coefficient eliminated; endorsed by National Kidney Foundation + American Society of Nephrology Joint Task Force. KDIGO 2024 staging: G1 ≥90, G2 60-89, G3a 45-59, G3b 30-44, G4 15-29, G5 <15. Multiply µmol/L creatinine by 0.0113 for mg/dL. **Not medical advice — needs clinical context (proteinuria, BP, comorbidities).**