Google Merchant Center Dimensional Shipping Starts April 2015

We’ll let you hear it directly from Google:

In the US, major shipping carriers recently began calculating many of their shipping rates based on the dimensional weight of a package rather than just the actual weight. These dimensional weight rates take into account the weight, height, length, and width of a package.

Today, we’re introducing support for dimensional weight shipping rates for carrier-calculated shipping methods in Google Merchant Center. This update lets you define the dimensions of your packages used for shipping taking into account the length, width, and height of a package — in addition to the weight you already provide. We’ve created three new attributes that merchants can add to their product data to provide the dimensions of shipping packages for an item: ‘shipping length’, ‘shipping width’, and ‘shipping height’.

In a recent review of your Google Merchant Center account (Account ID 12308581), we have determined that you have specified one or more carrier-calculated shipping methods in your account. Merchants who have active carrier-calculated methods for the US may need to provide these three additional attributes in their product data in order to allow accurate shipping rate calculations based on dimensional weight. If you’re unsure if your carrier is using a new dimensional weight rate model, or whether your shipments will be impacted, please verify directly with your shipping carrier.

If your carrier has changed the way they calculate shipping rates, you will need to add the following three attributes for items utilizing carrier-calculated shipping rates based on dimensional weight:

‘shipping length’ – Length of the item for shipping.

‘shipping width’ – Width of the item for shipping.

 ‘shipping height’ – Height of the item for shipping.

Starting April 6th, 2015, we’ll begin verifying that merchants using carrier-calculated rates are providing accurate rates by including these new attributes when the shipping rate is calculated based on dimensional weight. If merchants do not add these new attributes, we’ll continue to calculate the shipping rate based on weight only, which could lead to inaccurate shipping rate calculations. Accounts with inaccurate shipping rates will be suspended from Google Shopping.

To learn more about using the new dimensional shipping attributes, please visit the Products Feed Specification at and select ‘United States’ at the top.

But it is not as easy as it seems …
The cost to ship is based on the actual box size not the size of the product.  So what they calculate and what your site might calculate could be different.  And then what?
“Accounts with inaccurate shipping rates will be suspended from Google Shopping”.
If you think that unlikely then be aware that Google does contact merchants in cases where their shipping calculations based on feed data does not match the site checkout calculations.  How do they know? Anyone’s guess. Maybe a customer complaint.  But once they are onto it, you have no choice but to make changes or be suspended.
Dimensional shipping is not a fast change to make so we recommend everyone be proactive rather than wait for their email.