eGFR (Estimated Glomerular Filtration Rate): Normal Range, High & Low Causes
What eGFR measures
eGFR is calculated from your creatinine, age and sex. It estimates how many millilitres of blood your kidneys filter per minute and is the standard way to stage chronic kidney disease.
eGFR reference ranges
| Category | Conventional units | SI units |
|---|---|---|
| G1: Normal or high | 90 or above | mL/min/1.73 m² |
| G2: Mildly decreased | 60 – 89 | mL/min/1.73 m² |
| G3a: Mild to moderate decrease | 45 – 59 | mL/min/1.73 m² |
| G3b: Moderate to severe decrease | 30 – 44 | mL/min/1.73 m² |
| G4: Severely decreased | 15 – 29 | mL/min/1.73 m² |
| G5: Kidney failure | Below 15 | mL/min/1.73 m² |
A diagnosis of chronic kidney disease needs reduced eGFR or kidney damage markers persisting for at least three months. eGFR naturally declines with age.
Common causes of a high result
- Rarely a concern; very high values can occur with early diabetes (hyperfiltration) or low muscle mass
Common causes of a low result
- Chronic kidney disease (diabetes, high blood pressure and glomerular disease are common causes)
- Acute kidney injury from dehydration, infection or medicines
- Urinary tract obstruction
- Heart failure reducing kidney blood flow
How to prepare for the test
No fasting needed. Your lab calculates it from a creatinine test.
How often to retest
At least yearly for people with diabetes, high blood pressure or known kidney disease, or as advised.
Track eGFR over time
Upload your reports and Labgist plots every eGFR result on one timeline, converts units and shows what changed.
Get the appFrequently asked questions
What is a normal eGFR?
90 mL/min/1.73 m² or higher. Values slowly decline with age, and 60 or above is common in older adults without kidney disease markers.
Does one low eGFR mean kidney disease?
Not by itself. Diagnosis requires the result to persist for three months or more, so clinicians repeat the test and often check urine protein too.
How is eGFR calculated?
From serum creatinine, age and sex using a formula such as CKD-EPI. It is an estimate, not a direct measurement.
Related tests
Sources
This page is general education and was last updated 2026-10-30. It is not a substitute for medical advice. See our editorial approach.