# Recommended Packaging at Checkout
URL: https://support.starshipit.com/articles/12219449620111-recommended-packaging-at-checkout
Canonical: https://support.starshipit.com/articles/12219449620111-recommended-packaging-at-checkout
Markdown: https://support.starshipit.com/articles/12219449620111-recommended-packaging-at-checkout.md
Updated: 2026-06-23

> For the complete documentation index, see [llms.txt](https://support.starshipit.com/llms.txt).

> Use recommended packaging to calculate optimal box sizes for accurate live shipping rates at Shopify and WooCommerce checkout.

## How it works

At checkout, Starshipit determines the most efficient packaging for an order using product dimensions and your saved package options. Here’s how the process works:

:::note
Recommended Packaging is available on Professional plans and above. For Shopify checkout, products need dimensions from the Product Catalogue with **Use on checkout** enabled, or dimensions supplied directly on the checkout request.
:::

1. **Customer adds items to their cart and proceeds to checkout**  
   The checkout process sends the cart details, including SKUs and quantities, to Starshipit.
2. **Retrieving product dimensions**  
   If your platform sends dimensions on the checkout request, Starshipit can use those dimensions. For Shopify, Starshipit does not look up Product or Product Variant dimension metafields during checkout-rate requests.
   If no dimensions are available on the checkout request, Starshipit matches SKUs to the Product Catalogue (if enabled for checkout) and uses those dimensions.
   Items without dimensions are treated as loose items. If all items lack dimensions, the default package is used.
3. **Selecting package options**  
   Starshipit retrieves available packaging from your account settings.
4. **Determining the optimal packaging**  
   The algorithm prioritises the fewest number of packages while ensuring all items fit.  
   If multiple packages could work, it selects the one with the least empty space to reduce costs.
5. **Sending package details to the courier**  
   The final package dimensions are sent to your courier to calculate shipping rates.
6. **Returning the shipping rate to checkout**  
   The calculated shipping cost is returned to checkout and displayed to the customer.

## Setup steps

1. **Ensure products have dimensions**   
   For Shopify checkout, set accurate dimensions in the Product Catalogue ([Set up Product Catalogue](/articles/integrations/product-catalogue/product-catalogue)). Shopify Product or Product Variant dimension metafields are used for imported orders, not checkout-rate dimension lookup.
2. **Enable Product Catalogue at checkout**
   Go to **Settings > Product Catalogue** and tick **Use on checkout**.
3. **Set your packaging dimensions**   
   Go to **Settings > Packaging** and enter your packaging dimensions.
4. **Enable Recommended Packaging for checkout**   
   Navigate to **Settings > Checkout Rates** ([Set up Checkout Rates](/articles/rates-at-checkout/set-up-guides/set-up-rates-at-checkout)) and select **Automatically Assign Packages based on dimensions**.

## FAQs

<!-- faq:start -->

<!-- faq:question -->Will these packages be remembered when orders import?<!-- /faq:question -->

Not automatically. Configure your packaging settings to match your checkout preferences.

<!-- faq:question -->What happens if my items don't have dimensions?<!-- /faq:question -->

If dimensions are missing, your default package will be used.

<!-- faq:question -->What if one item in an order doesn't have dimensions?<!-- /faq:question -->

This item will be treated as loose, and other items will be packaged excluding it.

<!-- faq:question -->What if my item dimensions are less than 1cm?<!-- /faq:question -->

Recommended Packaging does not support decimal dimensions. Product and package dimensions must be at least 1cm for the checkout calculation to work correctly.

If you sell items with dimensions under 1cm, use Shopify shipping profiles to control when live rates are offered, or review whether another checkout shipping setup is a better fit.

<!-- faq:question -->Which platforms currently support Recommended Packaging?<!-- /faq:question -->

Recommended Packaging is supported on:

* **Shopify** — requires Product Catalogue dimensions with **Use on checkout** enabled, or dimensions supplied directly on the checkout request
* **WooCommerce** — requires product dimensions set up in WooCommerce or the Product Catalogue

<!-- faq:end -->

## Additional resources

* [Automatically assign packages based on item dimensions (order import)](/articles/getting-started/how-to-guides/how-to-assign-packages-automatically-based-on-item-dimensions-recommended-packaging)
* [Import optional data from Shopify](/articles/integrations/shopify/shopify-import-optional-data#product-dimensions-metafields) for Shopify order import dimensions
* [How to set up Product Catalogue](/articles/integrations/product-catalogue/product-catalogue)
* [How to set up Checkout Rates](/articles/rates-at-checkout/set-up-guides/about-live-rates-at-checkout-supported-couriers)