eGFR Calculator
Estimated GFR using CKD-EPI 2021 (Race-Neutral) and MDRD.
mg/dL
Years (Must be 18+)
Note: Race is *not* used in the modern CKD-EPI 2021 equation.
Calculation Result
Estimated GFR (CKD-EPI 2021):
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mL/min/1.73m²
CKD Staging Interpretation
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CKD Stages (KDIGO)
| Stage | eGFR (mL/min/1.73m²) | Description |
|---|---|---|
| G1 | $\ge 90$ | Normal or high |
| G2 | $60 – 89$ | Mildly decreased |
| G3a | $45 – 59$ | Mildly to moderately decreased |
| G3b | $30 – 44$ | Moderately to severely decreased |
| G4 | $15 – 29$ | Severely decreased |
| G5 | $\lt 15$ | Kidney failure (requires dialysis or transplant) |
About GFR Calculator – eGFR Calc
Kidney function can be estimated by measuring how efficiently kidneys filter waste from blood. Important factors considered include age, gender, race, and serum creatinine levels. Age naturally affects filtration, as kidney efficiency tends to decline over time. Gender is included because differences in muscle mass influence creatinine, a waste product used to assess filtration. Race has sometimes been considered, with adjustments in older formulas for African American populations, though recent approaches often avoid race-based factors.
Serum creatinine, measured in milligrams per deciliter, reflects the amount of waste produced from muscle metabolism. Higher levels usually indicate reduced filtering ability, while lower levels often suggest stronger kidney performance. Using standard formulas, these inputs are converted into a value expressed in milliliters per minute per 1.73 square meters, allowing comparison across individuals regardless of size.
Values are interpreted in ranges to indicate kidney function status. Numbers above 90 are generally seen as normal. Values from 60 to 89 may suggest mild reduction if other indicators are present. Moderate reduction falls between 30 and 59, severe reduction from 15 to 29, and numbers below 15 signal critical failure. Tracking trends over time is crucial, as gradual declines can indicate progressive disease, prompting early strategies to preserve kidney performance.
Several online tools in U.S. clinical portals provide these estimations using established formulas such as MDRD (Modification of Diet in Renal Disease) or CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration). Both consider age, gender, and creatinine levels, but CKD-EPI is often preferred for its accuracy near normal ranges. Clinicians usually confirm results with lab tests and monitor electrolytes, blood pressure, and protein presence in urine to gain a complete picture of kidney performance.