Understanding Sales Tax Across Regions

For anyone selling to customers in more than one country -- the systems genuinely aren't the same.

US sales tax is the natural starting point for most readers coming from a US-based business, but it's genuinely a different kind of system from what follows -- it's charged only at the final point of sale, not at each stage of production. VAT works differently: it's collected incrementally at each stage of a supply chain, which changes how it should be modeled for pricing. GST-based systems (used in countries like India, Canada, and Australia) are their own third variant again. Comparing all three in sequence is the point here, not just calculating one.

Each step opens as its own tool -- download from one, upload into the next, same as any free tool on the site.