Protein Creatinine Ratio Calculator (Urine UPCR)

Calculate the urine protein-to-creatinine ratio (UPCR) from a spot urine sample. Enter urine total protein and urine creatinine in common lab units; results are shown in mg/g, mg/mg and mg/mmol.

Enter your values above — the result appears instantly. Nothing you type leaves your device.
Medical disclaimer: This calculator is intended for educational and informational purposes and does not replace professional medical advice, diagnosis, laboratory interpretation, or treatment. Laboratory methods and reference intervals vary. Always consult a qualified healthcare professional about your results.

How the Protein Creatinine Ratio Calculator works

The urine protein-to-creatinine ratio (UPCR) compares total protein with creatinine in a single urine sample. Because creatinine is excreted at a fairly steady rate, the ratio corrects for urine concentration and approximates the amount of protein excreted over 24 hours — without a timed collection.

UPCR measures all proteins in urine. For early detection of kidney damage, the albumin creatinine ratio is generally more sensitive.

Supported units

  • Protein: mg/dL, mg/L (÷ 10 = mg/dL), g/L (× 100 = mg/dL)
  • Creatinine: mg/dL, µmol/L (÷ 88.4 = mg/dL), mmol/L (× 1000 ÷ 88.4 = mg/dL)

Formula used

UPCR (mg/mg) = urine protein (mg/dL) ÷ urine creatinine (mg/dL)
UPCR (mg/g) = UPCR (mg/mg) × 1000
UPCR (mg/mmol) = urine protein (mg/L) ÷ urine creatinine (mmol/L)

A UPCR in mg/mg is numerically about equal to grams of protein per gram of creatinine (g/g), which roughly approximates grams of protein excreted per day.

Worked example

Urine protein 30 mg/dL and urine creatinine 100 mg/dL:

  • UPCR = 30 ÷ 100 = 0.30 mg/mg → 300 mg/g
  • Protein 300 mg/L ÷ creatinine 8.84 mmol/L ≈ 33.9 mg/mmol

Interpreting the result

KDIGO proteinuria categories based on PCR (educational):

CategoryPCR (mg/g)PCR (mg/mmol)KDIGO description
A1< 150< 15Normal to mildly increased
A2150–50015–50Moderately increased
A3> 500> 50Severely increased

Limitations

  • Lab methods, collection time (first-morning vs random), exercise, fever, infection and posture can affect results.
  • Very low or very high muscle mass changes creatinine excretion and therefore the ratio.
  • Results are usually confirmed with repeat testing; a 24-hour collection may still be requested in some situations.
  • A single value cannot diagnose kidney disease or any specific condition.

Frequently asked questions

UPCR estimates how much total protein is being lost in the urine, corrected for urine concentration. In mg/mg (g/g) it roughly approximates grams of protein excreted per day.

A 24-hour collection measures all protein over a full day, while UPCR uses one spot sample. UPCR is more convenient and correlates well, but the two can differ.

Protein in mg/dL, mg/L or g/L and creatinine in mg/dL, µmol/L or mmol/L. All values are converted internally before calculating.

Guidelines generally prefer ACR for detecting early kidney damage. UPCR may be used when total protein (including non-albumin proteins) is of interest. Your clinician will choose the appropriate test.
Medical disclaimer: This calculator is intended for educational and informational purposes and does not replace professional medical advice, diagnosis, laboratory interpretation, or treatment. Laboratory methods and reference intervals vary. Always consult a qualified healthcare professional about your results.