Creatinine is a waste product of normal muscle metabolism, cleared almost entirely by your kidneys. Because production is fairly steady, the blood level is used as an indirect measure of how well your kidneys are filtering.
Check your value
Reference range used: 0.7–1.3 mg/dL. Runs in your browser — nothing is stored.
mg/dL
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Wellness information, not medical advice. Reference ranges vary between laboratories and depend on age, sex and context. This page cannot diagnose anything — always read your result with the range printed on your own report, and discuss concerns with a doctor.
The catch is that creatinine depends heavily on muscle mass. A muscular person can sit above the reference range with entirely healthy kidneys, while someone with little muscle can have meaningfully reduced filtration and still look normal.
Why it matters
Creatinine on its own is a blunt instrument. It is most useful converted into eGFR — an estimate of filtration rate that adjusts for age and sex — and read as a trend over time.
What influences your creatinine
Muscle mass, the single biggest non-kidney influence on the result.
Intense exercise in the days before the test, which raises it temporarily.
Creatine supplementation, which can raise measured creatinine without any change in kidney function.
Hydration status — dehydration concentrates it.
High meat intake shortly before testing.
What to do with the result
Look at eGFR rather than raw creatinine — it is the number that adjusts for who you are.
If your result is slightly high and you lift weights, take creatine or trained hard that week, that context matters. Mention it rather than assuming the worst.
The trend across several tests is far more informative than a single value.
Common questions
What is a normal creatinine level?
Roughly 0.7–1.3 mg/dL for men and 0.6–1.1 mg/dL for women, though laboratories differ. Muscular people often sit at or slightly above the top of the range normally.
My result is in µmol/L — how do I convert?
Divide µmol/L by 88.42 to get mg/dL. So 75 µmol/L is about 0.85 mg/dL.
Does creatine supplementation affect the test?
Yes. It can raise measured creatinine without impairing kidney function. Tell whoever interprets the result that you supplement.
What is eGFR?
Estimated glomerular filtration rate — a calculation from creatinine, age and sex that estimates filtration in mL/min. Above 90 is generally considered normal.
See this marker in context
A single value tells you little on its own. PhisBio Lab reads your whole blood panel and shows how five body systems — including Kidneys — are doing together.