Re: Shipping rates / box size questions!

How can I assign specific box sizes for shipping certain items?

2 0 0

I need advice on how to set shipping rates and box sizes.

For example:

I have set the Store default box size at 9 x 6 x 2 inches

This works OK for a 5 oz item that fits in that box.

However sometimes I have a 4 pound item at 16 x 8 x 8 inches, this is coming up in calculated shipping rates as too little $, as it is using the smaller box size to get the USPS rate.


Is there a way to assign box sizes to particular items, or regulate shipping costs based on certain size and weight of packages..? THANKS

Replies 2 (2)

Shopify Partner
400 25 68

Hi, you cannot do that directly in Shopify. But there are a few workarounds. 

1. Consider creating different shipping profiles for different groups of products. Groups can be formed on the basis of products having similar dimensions and hence they cost similar to ship. Then you can add different shipping prices for different groups.

2. You can also opt for a third party app like ShipMagic. It will allow you to have granular control over you shipping rates. However, be informed that you need CCS to be enabled on your store for any shipping rate app to work.

Automate & bulk assign products to shipping profile: Auto Shipping Profiles: Shipr
Calculate accurate shipping rates: Shipping Calculator: ShipMagic
Hide, rename, reorder payment methods at checkout: Payment Customization: PayMix

Shopify Partner
504 52 85

Hi @Blackdogdiecast ,


When using Shopify Shipping, you are limited to configuring a single box size.


A workaround would involve configuring the product weight by taking into account the volumetric weight.


To calculate the volumetric weight for USPS, follow this formula:

Volumetric Weight = (Length x Width x Height in inches) / 166


For instance, in the example provided, where the dimensions are 16x8x8 inches:

Volumetric Weight = (16 x 8 x 8 / 166 = 1024 / 166 = 6.2 pounds.


Therefore, it is advisable to set the product weight at 6.2 pounds instead of 4 pounds.

Co-Founder / CEO @ PluginHive
Shipping Automation | FedEx shipping | Multi-carrier shipping | Shipment Tracking | Australia Post shipping