# eGFR Calculator (CKD-EPI 2021 Race-Free) Estimate glomerular filtration rate (eGFR) with the CKD-EPI 2021 race-free creatinine equation: eGFR = 142 × min(SCr/κ, 1)^α × max(SCr/κ, 1)^(−1.200) × 0.9938^Age × 1.012 if female, where κ = 0.7 (female) / 0.9 (male) and α = −0.241 (female) / −0.302 (male). This 2021 update (Inker et al., NEJM 2021) removed the race multiplier from the 2009 equation and changed the leading coefficient from 141 to 142. Returns a BSA-INDEXED eGFR for CKD staging (G1–G5); for drug dosing use un-indexed CrCl (Cockcroft-Gault). Valid for stable adults, not AKI/pregnancy/amputees/extremes. Not medical advice. > Canonical page: https://elysiatools.com/en/tools/egfr-ckd-epi - **Category:** Health - **Keywords:** egfr, CKD-EPI, CKD-EPI 2021, race-free, glomerular filtration rate, kidney function, CKD, chronic kidney disease, serum creatinine, nephrology, renal, Inker ## Overview The eGFR Calculator estimates glomerular filtration rate for stable adults using the CKD-EPI 2021 race-free creatinine equation. Enter age, sex, and serum creatinine in mg/dL to receive a BSA-indexed eGFR in mL/min/1.73 m² and an associated CKD stage. This tool is not medical advice. ## Inputs - **Age (years)** (number): Patient age in years. Must be ≥18 and ≤120. - **Sex** (select) - **Serum Creatinine (mg/dL)** (number): Serum creatinine in mg/dL. Must be positive. - **Decimal Places** (number) ## When to use - Estimate kidney filtration for CKD staging in a stable adult. - Review how age, sex, and serum creatinine affect an eGFR result. - Apply the CKD-EPI 2021 race-free equation consistently in clinical or educational calculations. ## How it works - Enter an age from 18 to 120 years, select male or female, and provide a positive serum creatinine value in mg/dL. - The calculator applies the CKD-EPI 2021 race-free creatinine equation, using sex-specific κ and α values. - It returns eGFR in mL/min/1.73 m² and assigns a CKD stage from G1 to G5. - Choose the number of decimal places for the displayed result; the default is 4. ## Use cases - Estimate and document eGFR for chronic kidney disease staging. - Teach the effect of age, sex, and serum creatinine on the CKD-EPI 2021 calculation. - Standardize repeat eGFR calculations for stable adult patients during clinical review. ## Frequently asked questions ### What equation does this calculator use? It uses the CKD-EPI 2021 race-free creatinine equation described by Inker and colleagues. ### What units should I enter for serum creatinine? Enter serum creatinine in mg/dL. ### What does the eGFR result represent? It is a body-surface-area-indexed estimate reported in mL/min/1.73 m² for CKD staging. ### Can I use this result for drug dosing? No. The result is BSA-indexed; drug dosing should use an appropriate un-indexed creatinine clearance method, such as Cockcroft-Gault. ### When should this calculator not be relied on? It is intended for stable adults and is not validated here for AKI, pregnancy, amputees, or body-size extremes. ## Related tools - [eGFR Calculator (MDRD Simplified)](https://elysiatools.com/en/tools/egfr-mdrd): Estimate glomerular filtration rate (eGFR) with the simplified 4-variable MDRD equation (2006 re-expressed, IDMS-traceable): eGFR (mL/min/1.73 m²) = 175 × SCr^−1.154 × Age^−0.203 × (0.742 if female) × (1.212 if Black). 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