Reading Your Kidney Test Results
A plain explanation of creatinine, eGFR, urea and urine protein, and how to read the results with your doctor.
Last updated: 2026-09-24
Your kidney function is checked with inexpensive blood and urine tests. The two that matter most are creatinine, converted into your eGFR, and the urine albumin test for protein.
The tests, in plain terms
- Creatinine — a waste product your muscles make, cleared by your kidneys
- eGFR — how well your kidneys are filtering, calculated from creatinine
- Urea — a second waste marker
- Urine albumin — the earliest sign of kidney damage
One number is not a diagnosis
Dehydration, diet, recent exercise and some medicines can nudge your numbers up or down. What your doctor looks for is the trend over time, not a single reading.
Frequently asked questions
What is a normal creatinine level?
Roughly 0.6–1.2 mg/dL for most adults, but it varies with muscle, age and sex — which is why eGFR is more useful.
Do I need to fast for these tests?
Usually not, unless your lab asks for it as part of a combined panel.