Urine Protein/Creatinine Ratio
Calculate PCR using a random urine protein and creatinine measurement to quantify proteinuria when 24-hour collection is impractical.
Laboratories often report mg/dL; some provide g/L.
Ensure units align with laboratory reporting.
How to Use This Calculator
Collect a random urine sample
Use a spot urine specimen—ideally first-morning—to reduce variability in protein excretion.
Enter laboratory values
Input urine protein and creatinine concentrations using the units reported by the lab. The calculator handles unit conversion.
Interpret proteinuria severity
Follow-up abnormal results with repeat testing, albumin-specific measurements, and nephrology referral when appropriate.
Formula
PCR (mg/g) = (Urine protein (mg/dL) × 10) ÷ Urine creatinine (g/L)
Urine creatinine (g/L) = creatinine (mg/dL) × 0.01
PCR (mg/mmol) = PCR (mg/g) ÷ 8.84
Full Description
Urine protein-to-creatinine ratio approximates daily protein excretion without the need for 24-hour urine collection. PCR correlates with CKD progression and cardiovascular risk. Persistent elevations warrant renin-angiotensin system blockade, sodium-glucose cotransporter-2 inhibitors in eligible patients, and nephrology evaluation for possible glomerular disease. Combine PCR with albumin-creatinine ratio and eGFR to stage CKD per KDIGO guidelines.
Frequently Asked Questions
Does PCR replace albumin-creatinine ratio?
PCR captures total protein; ACR specifically measures albumin. Use ACR for diabetes and hypertension screening, PCR for nephrotic syndrome assessment.
When should I obtain a 24-hour urine?
Perform 24-hour collection if PCR suggests nephrotic-range proteinuria, results are inconsistent, or precise quantification is required for research or transplant evaluation.
How do diuretics or hydration affect PCR?
Urine concentration changes can shift PCR. Interpret trends and repeat testing under steady hydration when variability is suspected.
Is PCR valid in pregnancy?
Yes, PCR helps diagnose preeclampsia. Thresholds differ (≥0.3 g/g). Use pregnancy-specific guidelines to interpret results.