ShipZip uses Shopify variant metafields to apply advanced shipping rules like:

• Volumetric Weight
• Length
• Width
• Height
• Volume

These values are not available by default in Shopify checkout, so you must define them manually using metafields.

Metafields Work Only in Shipping Rule Conditions:

Metafields (like Length, Width, Height, Volume, and Volumetric Weight) are used only to create conditions in shipping rate rules in ShipZip. They do not apply shipping rates directly and will not work anywhere else in the app.

Create Variant Metafields in Shopify:

1. Volumetric Weight Metafield:

Create a metafield for volumetric weight:

Step #1: Open Shopify Settings > Click on Settings (bottom-left corner)

Step #2: Go to Metafields and Select Variants > In Settings, click on Metafields and metaobjects > Under Metafield definitions, click on Variants

Step #3: Click on Add definition

Step #4: In the Name field, Enter Name for Volumetric Weight

Important: The key must be exactly volumetric_weight

Any change (like volumetricweight or Volumetric_Weight) will not work.

Step #5: Set Namespace & Key

After entering the name, Shopify will auto-generate a default key (like custom.volumetric_weight). You need to manually change this.

Click > on the highlighted namespace.

Step #6: Update Namespace & Key

• Replace the default value: custom.volumetric_weight
• With the correct value: shipzip.volumetric_weight

Important (Must Follow):

• Namespace must be exactly: shipzip
• Key must be exactly: volumetric_weight

Step #7: Next, select the type “One”

Step #8: Select >  the “Single line text”

Step #9: Click > Save

2. Length:

Create a metafield to define the product length, which can be used in shipping rules like length-based charges or restrictions.

Follow the same steps as Volumetric Weight to create metafields for the Length.

Important note: Namespace and key must be exactly shipzip.length Otherwise, the condition will not work.

3. Width:

Create a metafield to define the product width, which can be used in shipping rules like width-based charges or restrictions.

Follow the same steps as Volumetric Weight to create metafields for the Width.

Important: Namespace and key must be exactly shipzip.width Otherwise, the condition will not work.

4. Height:

Create a metafield to define the product height, which can be used in shipping rules like height-based charges or restrictions.

Follow the same steps as Volumetric Weight to create metafields for the Height.

Important: Namespace and key must be exactly shipzip.height Otherwise, the condition will not work.

5. Volume:

Volume is calculated using below metafield calculation:

Length × Width × Height = Volume

This means the Volume metafield depends on below metafields:

• Length
• Width
• Height

Important Notes:

• This applies to all metafield-based rules (Length, Width, Height, Volume, Volumetric Weight)
• Namespace and key must be exactly the same as required any change will break the condition
• Metafields are used only inside the Conditions section of shipping rate rules
• They will not work anywhere else in the app