How can I automate inventory for products sold in packs, boxes, and cases?

Shopify Apps

Topic summary

Need: Automate multi-level inventory for a product sold as packs, boxes, and cases with fixed conversions. Stock is received as cases; system should explode inventory into boxes/packs with correct costs and auto-handle mixed-unit sales (e.g., selling 13 boxes deducts 1 case + 1 box and moves the remaining 11 boxes into box stock).

Constraints: No “buy more, save more” pricing; current workflow requires manual “pack out” stock adjustments, causing online overselling when busy.

Proposed approaches:

  • Custom theme code: Keep inventory in base units and dynamically offer packs/boxes/cases, deducting equivalent base quantity on purchase.
  • Inventory app with stock linking: Create relationships between pack/box/case SKUs so a sale of one unit size auto-decrements the others (composite/linked inventory).
  • Custom solution: A developer shared a custom app with a demo video showing a similar workflow that could be adapted.

Status: No definitive off-the-shelf app identified in-thread. Discussion remains open. Key open items: automated receiving as cases with cost allocation, seamless conversion between units, and synchronized deductions across linked SKUs. Video demo is central for assessing the custom option.

Summarized with AI on December 27. AI used: gpt-5.
1

We are a retail brick and mortar store with eComm. I’m needing to find a way to automate our inventory. My dilemma… We sell products which are sold in Packs, Boxes, & Cases. I’ve not been able to find a way or app to help. To be honest, not even sure if this exists.

Example:

  • Product A:
    • Pack contains 5 widgets
    • Box contains 20 packs
    • Case contains 12 boxes

In the perfect world, I’m looking for something that when the product is setup in Shopify, the number of packs/boxes and number of boxes/case are entered. When inventory is received, it will be received as cases. The system will then handle putting each qty into the appropriate qty bucket along with appropriate cost for each.

What I need is something that when ‘Product A’ sells 13 boxes, it will automatically deduct 1 case and 1 box from inventory. The system/app would take the remaining boxes from the partial case sold and put it into the box qty. Based on the example above, 11 boxes would be put into box qty. I’m sure this question will be asked… There are no discounts for “the more you purchase the more you save” so typical bundle apps are not a good fit for us.

Currently, we receive product based on the number of boxes. When items sell we have to “pack out” boxes. Using the example above, if George purchases 15 packs then Fred purchases 6 packs, I have to complete a stock adjustment to pack out the box. Our problem is that when we are busy we do not have time to stop and complete a stock adjustment (deducting 1 box and adding 20 packs to inventory & adjustment cost if necessary), which means an online customer may be able to “purchase” a box we do not have in-stock because a pack out was not performed yet.

2

The best way to achieve this is to replace your quantity input with some custom code. The inventory will still be treated as individual items but if a box and case ordered, 13 items will be deducted from the inventory.

For example if you enter 100 into inventory for product A, you will be able to sell 20 packs or 5 boxes or 8 cases The code can calculate and display the available packs, boxes or cases to the customer.

3

I believe you would need an inventory app to create linkages between your products. Assuming your products, box, pack, box are all products in the inventory. When product A is purchased, the app will automatically deduct the inventory of the linked products.

4

Hi @LoriF1101 ,

We build a custom app to solve the similar issue, request you to check if this could help with some minor adjustment as per your need.

Let me know if you have any query or doubt…