Belt Length & Pulley Size Calculator

By Anowar

Reviewed by Jasmine

This Ahm belt length calculator helps you to calculate the belt length as well as driven pulley size of any machine by following values. You will need to enter the motor RPM, drive pulley size, center distance between pulleys, and the required RPM.

Both pulley Image

This tool is useful when you are calculating belt length and driven pulley size. Because, you will get the exact belt length and driven pulley size in mm or inches, which are based on the pulley center distance and the machine required RPM. You can also change the driven pulley size by changing the rpm and the motor pulley (drive pulley) size.

Results:

Drive Pulley Size:
Belt Length:
Driven Pulley Size:
Motor RPM:
Driven Pulley RPM:

How RPM and Belt Length are Calculated


To calculate RPM of a driven pulley use the following formula:

Driven Pulley RPM = (Motor RPM × Drive Pulley Diameter) ÷ Required Driven Pulley RPM

Belt length formula:

Belt Length = (π × (Drive Pulley Diameter + Driven Pulley Diameter) / 2) + (2 × Center Distance)

By adjusting the size of the pulleys, you can increase or decrease the speed of the driven pulley based on the motor's RPM.

Frequently Asked Questions

RPM stands for Revolutions Per Minute, which measures how many complete turns an object makes in one minute.

The driven pulley is the pulley that is turned by the belt, driven by the drive pulley, and which transfers motion to the connected machinery.
  • Drive Pulley: Connected to a motor power source.
  • Belt: Connects the drive pulley and the driven pulley.
  • Driven Pulley: It is connected to the machine that is being powered. It rotates as the belt moves, thereby transferring motion.
  • Belt length can be calculated using the formula: Belt Length = (π × (Drive Pulley Diameter + Driven Pulley Diameter) / 2) + (2 × Center Distance).

    Center distance refers to the distance between the centers of the drive and driven pulleys, which affects the belt length and tension.
    Author:
    Anowar:
    Hi, I am Anowar, and more than 10 years of experience and good knowledge of mathematical applications. We create user-friendly tools that are useful in our everyday calculations.