Great question — answering as the UphillTech team:
This answer is a little bit late, but i hope, i can help others that are struggling with the same issue. First i would recommend to set up all Shipping Rates and Taxes in Shopify. There are plenty of manuals to achieve this: https://help.shopify.com/manual/taxes#general-process-to-set-up-taxes https://help.shopify.com/manual/shipping/rates-and-methods/calculated-rates After this there are different possibilities to calculate your shipping and tax cost. Your shipping cost can you get via the active_shipping API, which can be found here: https://github.com/Shopify/active_shipping Or the following Shopify Application: https://apps.shopify.com/boxify However, you may need to know size and...
Full answer by Neyxo: https://stackoverflow.stackexchange.com/a/46766440 (CC BY-SA 4.0).
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