What does my eGFR result mean on my kidney labs?
Short answer: eGFR (estimated glomerular filtration rate) is your doctor's best estimate of how well your kidneys are filtering waste from your blood. It's a number — higher is better — calculated from your creatinine level plus your age and sex. It's reported in mL/min/1.73m², which just means "filtering rate adjusted to a standard body size."
What it usually means on your report
Here's the rough map clinicians use (your doctor interprets your number in context — this is the general framework, not a diagnosis):
- 90 or above: normal filtration
- 60–89: mildly reduced — often completely normal for older adults; only meaningful alongside other signs of kidney stress
- 45–59: mild-to-moderate reduction
- 30–44: moderate-to-severe reduction
- 15–29: severe reduction
- Below 15: kidney failure range
Three things most people aren't told: (1) eGFR is an estimate, not a direct measurement; (2) one low reading doesn't diagnose anything — chronic kidney disease is defined by persistently low results over at least three months; and (3) the number naturally drifts down with age, so the same value means different things at 40 and at 75. Dehydration, intense exercise, a very high-protein meal, or unusual muscle mass can all move the number without your kidneys having changed.
What it does NOT mean
- A result in the 60s or 70s does not automatically mean kidney disease — especially in older adults. Context (age, trend, urine tests) is everything.
- One low reading does not equal a diagnosis. Clinicians look for a sustained pattern, usually confirmed with repeat testing and a urine protein check.
- eGFR does not capture the whole picture. Kidney damage can show up in urine testing before eGFR drops at all.
When to ask your clinician
- "My eGFR is [number] — is that expected for my age, or should we look closer?"
- "Should we repeat this test to establish a trend?"
- "Would a urine protein test add useful information here?"
This is a plain-English explanation of terms, not medical advice. Talk to your clinician about what your results mean for you.