"Load size" refers to the amount or volume of something that can be carried or accommodated by a vehicle, machine, or container. It indicates how much can be transported or held at a given time. Full definition
Because of this you are able to use a very small quantity in the amount of 1 to 4 tablespoons depending on load size and machine type. (diaperjunction.com)
The most accurate method of determining load size is by weight in relation to your washer capacity. (thespruce.com)
It even includes an automatic optimal setting option that oversees the washing cycles depending on laundry load size. (bgr.com)