Order boxing

Overview

Order boxing lets you define the physical boxes you use for shipping and allows the Transdirect app to calculate the optimal way to pack a customer’s order into those boxes. Instead of quoting each product as a separate parcel, the app groups items into your defined boxes and calculates shipping based on the packed result.

This produces more accurate quotes — especially for orders with multiple small items that would otherwise be quoted individually.

How it works

When a customer’s cart is sent for quoting, the app:

Takes each item’s weight and dimensions from the cart
Attempts to fit items into your defined box sizes, starting with the smallest box
Calculates the volumetric weight of each packed box
Sends the packed boxes (rather than individual items) to the Transdirect API for quoting

The result is a quote based on the actual boxes you will ship, rather than the individual product dimensions.

Defining boxes

You can define up to five box sizes. Each box requires the following dimensions:

Field	Unit	Description
Name	—	A label for the box (e.g. “Small”, “Medium”, “Large”)
Length	cm	Internal length of the box
Width	cm	Internal width of the box
Height	cm	Internal height of the box
Max weight	kg	Maximum weight the box can hold

Open boxing settings

In your Shopify admin, go to Apps → Transdirect → Order Boxing.
Add a box

Click Add Box and enter the box name, internal dimensions, and maximum weight.
Repeat for additional boxes

Add up to five boxes. Define a range of sizes that covers your typical order sizes — from small single-item orders to large multi-item orders.
Save settings

Click Save. The app will begin using your box definitions for all new quotes.

Volumetric weight calculation

Couriers charge based on the greater of actual weight or volumetric weight. The app calculates volumetric weight for each packed box using the standard formula:

Volumetric weight (kg) = Length (m) × Width (m) × Height (m) × 250

For example, a box measuring 40cm × 30cm × 20cm:

Volumetric weight = 0.40 × 0.30 × 0.20 × 250 = 6kg
If the packed items weigh 3kg, the courier charges based on 6kg (volumetric)

See items and packaging for more details on volumetric weight.

Minimum fill

The minimum fill setting controls how much of a box must be filled before the app moves to a larger box size. This prevents the app from using an oversized box for a small order.

Setting	Description
Minimum fill percentage	The minimum percentage of the box volume that must be occupied before the box is used.

For example, with a minimum fill of 20%, the app will not use a “Large” box if the items only occupy 10% of its volume — it will try a smaller box first.

Best practices

Define boxes that match your real packaging

Use the actual box sizes you stock. If you use three standard box sizes in your warehouse, define those three sizes in the app. Adding hypothetical sizes leads to inaccurate quotes.

Include a range of sizes

Define at least a small, medium, and large box to cover the range of order sizes your store typically handles. This gives the packing algorithm the best chance of finding an efficient fit.

Test with representative orders

After configuring your boxes, test the quoting process with a few typical orders to verify the packed results make sense. Check that the box selections and quoted prices align with your expectations.

Monitor for oversized items

If a product is larger than your biggest defined box, it will be quoted as an individual item outside of the boxing system. Make sure your largest box can accommodate your largest commonly ordered product.

Next steps

Configure multipickup and frequent rates for high-volume shipping discounts
Set up shipping rules to further control rates and courier availability