Estimate glomerular filtration rate (eGFR) from serum creatinine. For adults 18 and older, the primary result uses the current race-free 2021 CKD-EPI creatinine equation. The comparison table also shows three older equations for historical context. The children tab uses bedside Schwartz.
How to use the result
Use serum creatinine from a recent test and select the unit printed by the laboratory. The adult equation accepts ages 18 and older. Compare the headline value with the equation name on the laboratory report before comparing two dates; a switch from a legacy equation to the 2021 equation can change the number even when creatinine is unchanged.
The displayed G categories are numerical ranges only:
| G category | eGFR (mL/min/1.73 m²) |
|---|---|
| G1 | 90 or higher |
| G2 | 60–89 |
| G3a | 45–59 |
| G3b | 30–44 |
| G4 | 15–29 |
| G5 | Below 15 |
A category is not a diagnosis by itself. G1 and G2 in particular require other evidence of kidney damage for chronic kidney disease classification, and chronicity matters across all categories.
Examples
Adult default: 0.9 mg/dL, age 50, male
The 2021 CKD-EPI result is 104.0 mL/min/1.73 m², in the G1 numerical range. The legacy table shows 99.2 from 2009 CKD-EPI, 89.3 from MDRD, and 120.3 from Mayo. Entering the equivalent 79.56 µmol/L gives the same results after conversion.
Adult woman: 0.9 mg/dL, age 50
The race-free 2021 CKD-EPI result is 77.9 mL/min/1.73 m², in the G2 numerical range. That range alone does not establish CKD.
Child: 0.9 mg/dL and 110 cm
Bedside Schwartz gives 50.5 mL/min/1.73 m². Adult G categories are not applied on the children tab.
Formula
Serum creatinine is converted to mg/dL (µmol/L ÷ 88.4). The 2021 adult
equation is:
eGFR = 142 × min(SCr/κ, 1)^α × max(SCr/κ, 1)^−1.200
× 0.9938^age × 1.012 (if female)
κ = 0.7 female or 0.9 male
α = −0.241 female or −0.302 male
The result is standardized to mL/min/1.73 m². The older 2009 CKD-EPI and MDRD comparisons can change with the legacy race input; the 2021 result does not.
Bedside Schwartz / CKiD (children)
eGFR = 0.413 × height (cm) / SCr (mg/dL)
eGFR is an estimate rather than a direct measurement or diagnosis. Do not use this page to start, stop, or change a medicine. A clinician may consider the laboratory equation, repeat results, urine albumin, body size, muscle mass, diet, medicines, and cystatin C when a decision depends on the number.