Understanding the Large Cart Shipping Rule

What Is the Large Cart Shipping Rule?

Eniture Technology publishes many apps designed to present LTL freight, parcel, and truckload freight shipping rates in the checkout process of the following e-commerce platforms:

• BigCommerce
• Magento
• Shopify
• Wix
• WooCommerce

Many of these have, or are in the process of receiving, support for Shipping Rules. Shipping Rules allow an app's subscriber to modify its operation so that an alternate outcome occurs.

The Large Cart shipping rule is relevant only when:

• An app that provides parcel shipping rates is in use;
• The Box Sizes feature is enabled.

The Large Cart shipping rule by-passes the Box Sizes packaging algorithm when more than a specified number of items are in the shopping cart. When triggered, shipping rates are based on the weight of the shopping cart.

Why is the Large Cart Shipping Rule Necessary?

The Box Sizes feature uses an iterative algorithm to identify a package solution using the list of available boxes, and the weight and dimensions of the items in the shopping cart. In most cases, the algorithm executes in a few seconds. However, when the shopping cart contains a large number of items, and there are many boxes to evaluate, the algorithm's execution time can exceed the time available on the e-commerce platform. When this occurs, visitors will see a message informing them of one of the following:

• Shipping rates aren't available.
• We don't ship to your address.

The Large Cart shipping rule exists to bypass the Box Sizes packaging algorithm when its execution time is likely to exceed the time available on the e-commerce platform. When triggered, shipping rates are based on the shopping cart weight, thereby reducing the time required to display shipping rates on the checkout page or elsewhere on the e-commerce website.

How Many Boxes and/or Items Is Too Many for the Packaging Algorithm?

There aren't strict numbers that predict when the package algorithm's execution time will exceed the time available on the e-commerce platform. The factors that influence the execution time are:

• The number of available boxes.
• The number of items in the shopping cart that are to be boxed.
• The boxing properties of the items in the shopping cart, such as allowing for the items to be rotated for placement.

The following are general guidelines for each of the influencing factors.

Number of Available Boxes

Try to limit the number of available boxes to twenty (20) or fewer. Remember that identifying a box size should occur only if the box is used to package multiple items. If an item is inventoried in the same packaging it will ship in, or if it ships in a dedicated box, do not add it to the list of available boxes.

The Box Sizes feature in many apps allows a box to be defined and assigned for use with a specific group of products. This case is a smaller task for the packaging algorithm, and can safely permit the addition of boxes above twenty (20). For example, a merchant may have a product catalog of 40,000 items and 20 defined boxes that are generally available for use. Of the 40,000 items, there may be 500 that require the use of one of 4 product-specific boxes. When the shopping cart contains only items that are in this subset of 500, then this is easily handled by the packaging algorithm. And in this case, when considering only the influence of the number of boxes, having twenty four (24) instead of twenty (2o) boxes is not a concern.

Limiting the number of generally available boxes to twenty (20) is not a strict requirement. There are merchants that successfully exceed this recommendation. In their cases, their experience with the other influencing factors allows for it.

Number of Items in the Shopping Cart

The number of items that can be in a shopping cart before the packaging algorithm's execution time exceeds what is available on the e-commerce platform is directly correlated with the number of available boxes. The fewer the boxes, the more "to-be-boxed" items can be in the shopping cart.

In general, if you are expecting shopping carts that exceed 200 items, and you have more than twenty (20) boxes, it's likely that the packaging algorithm's execution time will take too long. The execution time may be too long when there are fewer than 200 items and 20 boxes, depending on other factors. If you have shipping carts with a large number of items and shipping rates aren't present during checkout, it may be an indication that you need to set a lower threshold for the Large Cart shipping rule, or compensate for it another way, such as reducing the number of boxes.

Boxing Properties

The product-level settings include a setting to allow the packaging algorithm to rotate the item for placement in a box. This setting gives the packaging algorithm the most flexibility for arriving at a packaging solution. It also frees up the packaging algorithm to perform additional iterations while arriving at the optimal packaging solution, lengthening the execution time.

Although the rotational boxing property can lengthen the algorithm's execution time, its benefits outweigh its overhead. It's best to focus attention on limiting the number of boxes, and establishing a Large Cart shipping rule that helps avoid messages to visitors that a shipping rate isn't available, or that shipping is not available to their address.

How to Select the Large Cart Settings

Because there are multiple co-dependencies, the value to use for the Large Cart shipping rule differs between stores. To determine what's best for your store, start with the recommended thresholds in this document. Limit the number of boxes to twenty (20), and set the Large Cart shipping rule to trigger at 200 items. Check whether shipping rates are being returned. Check the logs for the latency interval. Depending on the outcome, you can make changes up or down as needed to achieve a reliable outcome.