Enter the larger belt diameter (in) and the smaller belt diameter (in) into the Belt Ratio Calculator. The calculator will evaluate and display the Belt Ratio. 

Belt Ratio Formula

The following formula is used to calculate the Belt Ratio. 

BLR = LD / SD 
  • Where BLR is the Belt Ratio
  • LD is the larger belt diameter (in) 
  • SD is the smaller belt diameter (in) 

To calculate the belt ratio, divide the larger belt diameter by the smaller belt diameter.

How to Calculate Belt Ratio?

The following example problems outline how to calculate Belt Ratio.

Example Problem #1:

  1. First, determine the larger belt diameter (in).
    • The larger belt diameter (in) is given as: 2.5.
  2. Next, determine the smaller belt diameter (in).
    • The smaller belt diameter (in) is provided as: 1.5.
  3. Finally, calculate the Belt Ratio using the equation above: 

BLR = LD / SD 

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

BLR = 2.5 / 1.5  = 1.667


Example Problem #2: 

For this problem, the variables required are provided below:

larger belt diameter (in) = 6

smaller belt diameter (in) = 3

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

BLR = LD / SD  = ?