Variants

In Shopify, a product consists of up to three options (e.g. size, color, material) whose combinations form the variants. Each variant is an independently sellable unit with its own SKU, price, inventory, weight and, ideally, its own image. Since Shopify raised the variant limits, even large matrices with up to 2,048 variants per product can be modeled.

The modeling question matters more than it looks: what is a variant of the same product, and what is a separate product? Rule of thumb: variants represent genuine purchase decisions within one product (size, color). Different models or product lines are separate products — otherwise search, filters, feeds and SEO all suffer.

Cleanly modeled variants are the prerequisite for working inventory logic, marketplace feeds and ERP synchronization. In migrations from systems with different variant logic (Magento's configurable products, for instance), variant mapping is one of the critical design decisions.