What is GFR and what does it tell you?

GFR stands for glomerular filtration rate, and it is one of the most important numbers used to assess how well your kidneys are working. It tells you how much blood your kidneys filter each minute, helping detect early signs of kidney function decline.

In a healthy adult, the GFR is typically around 90 to 120 milliliters per minute (mL/min). This means the kidneys are filtering that amount of blood every minute. If your GFR is lower than normal, it may suggest that your kidneys are not removing waste from the blood as efficiently as they should.

GFR is not measured directly but is estimated using a blood test, usually based on your creatinine level, along with other factors like age, sex, and body size. The result is called estimated GFR or eGFR, and it is a routine part of most kidney function tests.

Here is what eGFR can indicate:

• A value above 90 is usually considered normal (if no other signs of kidney issues are present).
• A value between 60 and 89 may still be normal but should be monitored over time.
• A value below 60 for more than three months may suggest chronic kidney disease.
• A value below 15 may indicate kidney failure and the need for treatment such as dialysis.

eGFR is used by doctors to stage kidney function, monitor progress, and guide treatment decisions. It is also helpful for identifying problems before symptoms appear, which makes early testing so important—especially for people with high blood pressure, diabetes, or a family history of kidney problems.

Knowing your GFR gives you a clear picture of your kidney health, even if you feel completely fine. It is a simple number with powerful insight.

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