The calculation object contains tax rate information. A calculation also includes a calculation_id that you’ll use to record a transaction for filing.

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When to create Calculations

Calculations should be used any time you need to calculate sales tax before charging a customer for a transaction. Most e-commerce clients will submit a POST to /tax/calculations during their checkout flow after the end customer has submitted their address, but before collecting payment. core flow

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How to create Calculations

We return both the aggregate tax information as well as a detailed breakdown for each line item. Many users will just use the total_tax_amount to identify what to charge a user, but you will always have the details as you need them.

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Further documentation

The full documentation for creating calculations is on this page.