Belt Length Calculator

How do you Calculate Belt Length?

Calculating the length of a belt will require a few different values. The three variables required includes:

• Larger pulley diameter


• Smaller pulley diameter


• Distance between the two pulley's center

1. BL = Belt Length


2. D1 = First pulley's diameter (in inches)


3. D2 = Second pulley's diameter (in inches)


4. D3 = Distance between two pulley's centers (in inches)

Understanding Your Results

The result from using this tool will be a single value which represents the length of the belt that should fit properly around the pulley system that you entered. It is displayed in inches by default. This can be changed to another unit if needed and will automatically convert it to that new unit.

How to Use the Belt Length Tool

We wanted to make it as easy as possible to calculate the length of a belt in a two-pulley system. The steps required to use our tool includes:

1. Enter the larger pulley's diameter and select the appropriate unit of measurement if inches is not it.


2. Enter the smaller pulley's diameter and select the appropriate unit of measurement if inches is not it.


3. Enter the distance between the two pulley's centers and select the appropriate unit of measurement if inches is not it.


4. Hit calculate and get your belt length result in under a second!

Example Calculation

Let's say you have a vehicle that is aided by a two-pulley system. You measure the diameter of the larger pulley and find it to be 7 inches. You then measure the smaller pulley and find it to have a diameter of 5 inches. The distance between the two center points of the pulleys is 9 inches according to your measurement. We can now plug 7 into the larger pulley field, 5 into the smaller one and 9 into the final field. We do not need to change any of the units since they are all in inches by default.

We can now hit calculate to get our answer. We find that the belt length is 36.96 inches. If we need to get the length in centimeters we can select that unit from the dropdown menu and see that the belt length would then be 93.88 centimeters.