Enter the total BUN (mg/dL) and the plasma Creatinine (mg/dL) into the Bun Creatinine Ratio Calculator. The calculator will evaluate and display the Bun Creatinine Ratio. 

Bun Creatinine Ratio Calculator

Enter any 2 values to calculate the missing variable

Bun Creatinine Ratio Formula

The following formula is used to calculate the Bun Creatinine Ratio. 

BCR = TB / PC
  • Where BCR is the Bun Creatinine Ratio (unitless; often written as a ratio such as 25:1)
  • TB is the total BUN (mg/dL) 
  • PC is the plasma Creatinine (mg/dL) 

To calculate the BUN/creatinine ratio, divide the total BUN by the total plasma creatinine.

How to Calculate Bun Creatinine Ratio?

The following example problems outline how to calculate Bun Creatinine Ratio.

Example Problem #1:

  1. First, determine the total BUN (mg/dL).
    • The total BUN (mg/dL) is given as: 125.
  2. Next, determine the plasma Creatinine (mg/dL).
    • The plasma Creatinine (mg/dL) is provided as: 5.
  3. Finally, calculate the Bun Creatinine Ratio using the equation above: 

BCR = TB / PC

The values given above are inserted into the equation below and the solution is calculated:

BCR = 125 / 5 = 25 (unitless)


Example Problem #2: 

For this problem, the variables required are provided below:

total BUN (mg/dL) = 160

plasma creatinine (mg/dL) = 7

Test your knowledge using the equation and check your answer with the calculator above.

BCR = TB / PC = ?