# How to Calculate Forklift Capacity With Attachments

Calculating the forklift capacity is critical for safely and efficiently operating equipment. To start, let’s define what load center is of a forklift. The load center is the horizontal distance from the center of mass to the forklift itself, or, in simpler terms, the middle of the load.

The load center is relevant as it specifies how far you can place your mass before the forklift will be over in either direction.

## Calculate Forklift Capacity

To start, each lift truck is given specific ratings that specify relevant information, these are typically found on the truck name plate. This same principle applies for attachments. The first rating will give the maximum fork height, and the second rating will give the increased capacity amount at a lower fork height.

Each attachment is given a reduction factor that is to be used to calculate the forklift capacity.

Example 1: The image below gives an example of a capacity name plate where the information is already filled out. The attachment that is applied has a reduction factor of 1,500 lbs. Given that the original maximum capacity, without the attachment, is 8,000 lbs, we simply do 8,000 – 1,500 = 6,000 lbs to calculate forklift capacity with the attachment.

Example 2: Technical data sheets give very helpful information as to how to calculate the capacity. Let’s say you add a paper roll clamp on a gas, cushion tire, 6,000 lb. truck that has a mass of 102/228. This would bring us to the last row of the technical data sheet.

The capacity with forklift forks is 4,150 lbs (24″ load center, 228″ fork height) and a rated capacity of 6,000 lbs (24″ load center, 228″ height). For this scenario, let’s say it is given that the reduction factor for a 6,000 lb truck is 1,700 lbs. Because there are more than one rated capacities, you take the lowest after applying the reduction factor. 6,000 – 1700 = 4,300 lbs and 4,150 – 1700 = 2,250