Know your BUN/Cr Ratio. Know your health.
Test your BUN/Creatinine Ratio and 100+ other biomarkers in a single blood draw.
Normal range: 10 – 20 (lower is better)
The BUN/creatinine ratio helps your doctor figure out why kidney markers might be off. A high ratio with elevated BUN suggests the kidneys themselves are healthy but not getting enough blood flow (often from dehydration). A normal ratio alongside elevated creatinine points to actual kidney disease. It is a diagnostic clue, not a standalone test.
A normal BUN/Cr Ratio is 10 – 20. Lower is better.
A high BUN/creatinine ratio usually indicates dehydration or reduced blood flow to the kidneys (called prerenal azotemia), meaning the kidneys are structurally healthy but underperfused. GI bleeding and high-protein diets also raise BUN selectively, pushing the ratio up.
A low ratio may indicate liver disease (reduced urea production), malnutrition, or rhabdomyolysis (muscle breakdown floods the blood with creatinine). Because this is a derived ratio, the same lifestyle factors and medications that affect BUN and creatinine individually drive changes here. Staying hydrated is the single most impactful thing you can do.
BUN/Cr Ratio is most highly correlated with BUN and HDL Cholesterol. Here are the top biomarkers correlated with BUN/Cr Ratio, based on 500,000 tests done by Empirical Health.
The percentage shows how strongly two biomarkers move together. A higher number means the relationship is stronger. Green = rises and falls together. Orange = one rises as the other falls.
You can test your BUN/Cr Ratio for $190 as part of Empirical's comprehensive health panel, which includes 100 biomarkers.
You can measure your BUN/Cr Ratio for at 2,200+ testing locations across the US. Click below and enter your zip code to browse locations near you.
Test your BUN/Creatinine Ratio and 100+ other biomarkers in a single blood draw.