The plugin analyzes the cart contents and attempts to fit products into predefined boxes based on their dimensions, weight, empty box weight, and padding. The packing result is not used to calculate shipping costs independently; instead, it is passed to Flexible Shipping. There, it can be utilized in rules based on the Box type, the Number of boxes, or the No matching boxes scenario (when products cannot be packed into any available boxes).
When products are successfully packed
If the cart contents can be fitted into the defined boxes, the plugin passes information regarding the box types used and their total count to Flexible Shipping.
In this scenario:
- The Box type condition can match rules based on the actual boxes used.
- The Number of boxes condition is evaluated based on the number of packages generated by the packing algorithm.
- Additional costs calculated per box are applied according to the packing result.
- The No matching boxes rule will not be triggered because the packing process was successful.
When products cannot be packed
If the cart contents do not fit into any of the available boxes, the plugin flags the case as No matching boxes and passes this information to the Flexible Shipping rules.
In this scenario:
- The Box type condition will only match rules where the No matching boxes option is explicitly selected. Rules based on specific box types will not be met.
- The Number of boxes condition will not be matched, even if its range includes 0, as this condition is treated as “unmet” for an unpackable cart.
- Additional costs based on the number of boxes will use a value of 0, meaning no additional fee will be charged.
In practice, if no box match is found, only rules explicitly handling No matching boxes will be applied.
Additional cost based on the number of boxes
In Flexible Shipping rules, you can apply an additional cost dependent on the number of boxes used to pack the order. This value is calculated based on the number of packages created by the packing algorithm.
This mechanism can be used with any rule condition as well as with the Always condition. If a Box type condition is also present in the same rule, only the boxes corresponding to the selected types are taken into account when calculating the additional cost. If the products cannot be packed, the value used for the additional cost calculation is 0, so no extra charge will be added.