Estimated glomerular filtration rate (eGFR) information

What is estimated glomerular filtration rate (eGFR)?

The estimated glomerular filtration rate, or eGFR, is a measurement calculated from blood test results that helps doctors to understand how well your kidneys are working and identify if you have kidney disease (CKD).

By measuring the levels of a waste product called creatinine in your blood, along with other factors such as your age and biological sex, a doctor calculates the estimated glomerular filtration rate (eGFR). This value indicates how many millilitres of your blood the kidneys are cleaning per minute.

Healthy kidneys typically filter more than 90 ml each minute (this figure is adjusted for body size). A lower rate may indicate chronic kidney disease (CKD).

Why eGFR testing is needed

In its early stages, chronic kidney disease (CKD) often presents without symptoms.

If you're at increased risk, such as having high blood pressure, diabetes, cardiovascular disease, a family history of kidney disease, acute kidney injury or other conditions that affect your kidneys, your doctor might suggest a blood test to determine your eGFR.

In the later stages of CKD, symptoms may appear and a blood test to look at eGFR might be necessary if you experience any of the following:

A change in how often you urinate

Feeling more tired

Nausea

Loss of appetite and losing weight

Being short of breath

Blood in your urine

Itching

Swelling in your feet, ankles, or hands

Muscle cramps

Headaches

Disrupted sleep

Erectile dysfunction

What does an eGFR test involve?

Your eGFR is calculated from a simple blood test that can be done any time of day. A healthcare provider will draw a blood sample from a vein in your arm with a small needle. Once inserted, a small amount of blood is collected in a small container. You might feel a sting during insertion or removal of the needle.

Usually, you can go back to your day-to-day activities following a blood test.

What do eGFR test results mean?

Your eGFR result is given as a number. This value indicates how well the kidneys are functioning, with a higher number indicating better kidney function.

If your eGFR results suggest you have chronic kidney disease (CKD), this is graded from Grade 1 (G1) to Grade 5 (G5). The higher the grade the worse your kidney function is.

An eGFR of 90ml/min or higher indicates a normal range. However, if other tests have identified signs of kidney damage this is classified as G1.

An eGFR of 60-89ml/min indicates a small reduction in kidney function. If other tests have identified signs of kidney damage this is classified as G2.

An eGFR of 45 to 59ml/min is classed as G3a and indicates a small to moderate reduction in kidney function.

An eGFR of 30 to 44ml/min is classed as G3b and indicates a moderate to severe reduction in kidney function.

An eGFR of 15-29ml/min is classed as G4 and indicates a severe reduction in kidney function.

An eGFR below 15ml/min is classed as G5, where the kidney function is almost completely lost leading to kidney failure.

What is a normal eGFR number?

A normal eGFR is generally considered to be 90 ml/min or higher.

Your eGFR can naturally decrease with age, and a slightly lower eGFR may be normal for older adults.

It’s also important to view eGFR results in context with other tests and overall health.

Understanding your eGFR results

If your eGFR is lower than normal, it may not necessarily mean you have kidney disease. Your doctor will consider these factors, along with your medical history, symptoms, and other test results, before making a diagnosis.

For more information on understanding your test results, please visit our dedicated page understanding test results.

Reviewed August 2025