Kidney
eGFR (Estimated Glomerular Filtration Rate) — what it measures
For understanding, not diagnosis. Reference ranges differ between laboratories; the ranges on your own report, and your doctor’s reading of them, always come first.
What it measures
eGFR is not measured directly; it is calculated from your creatinine result plus your age and sex to estimate how much blood your kidneys filter per minute. It is the number most often used to summarise kidney filtering function on a report.
What can skew it
Anything that shifts creatinine, including creatine supplements, big changes in muscle mass or dehydration, will also shift the eGFR estimate.
Reference ranges
The calculation method and reference ranges vary between laboratories and populations, so treat eGFR as an estimate to discuss with your clinician, not a standalone verdict.
Medical disclaimer: This page is educational only. It cannot tell you whether your result is normal or what to do about it — that is a decision for your doctor, with your full history.