UPCR / PCR Calculator (Urine Protein-to-Creatinine Ratio)
Estimate protein loss in urine using a spot sample, with results in mg/g, mg/mmol, and g/g.
Last updated on: December 14, 2025
Calculate UPCR / PCR
What is the urine protein-to-creatinine ratio (UPCR/PCR)?
UPCR (also called PCR) compares the amount of total protein in a spot urine sample to urine creatinine from the same sample.
Because creatinine excretion is relatively steady, the ratio helps correct for urine dilution and can approximate daily protein loss.
Results may be reported as mg/g, mg/mmol, or simply as a numeric ratio (g/g or mg/mg).
Why is UPCR useful?
- Screening and monitoring kidney disease and proteinuria.
- Follow-up of glomerular diseases and treatment response.
- A faster alternative to 24-hour urine protein in many situations.
- In pregnancy, a UPCR ≥0.3 (≈300 mg/g) can support the diagnosis of proteinuria when evaluating preeclampsia.
How to interpret your result
Normal to mildly increased:
Typically <150 mg/g (≈ <17 mg/mmol). Persistent elevation should be confirmed with repeat testing.
Moderately increased proteinuria:
About 150–500 mg/g. Consider clinical context and confirm persistence with follow-up testing.
Severely increased proteinuria:
>500 mg/g. Often warrants prompt clinical evaluation, especially if accompanied by hematuria, edema, or reduced kidney function.
Nephrotic-range proteinuria:
≥3500 mg/g (≥3.5 g/g). This level is commonly associated with nephrotic-range protein loss and needs urgent medical assessment.
Important notes & limitations
UPCR is a helpful estimate, but results can vary with exercise, fever, dehydration, urinary tract infection, or timing of the sample.
- Abnormal results should be confirmed (repeat testing) if clinically appropriate.
- Albumin-to-creatinine ratio (ACR) is often preferred for early CKD risk stratification when available.
- In pregnancy, UPCR thresholds differ (commonly ≥0.3). Always interpret with obstetric guidance.
This page has been medically reviewed by Dr. Khoulah Attia – PharmD, Immunology Specialist.