ASIN (Amazon Standard Identification Number)
Definition
Amazon's 10-character product ID that identifies each item in its catalog. Every listing, variation and sale on Amazon traces back to an ASIN.
Want a deeper explanation?
ASINs are how you connect Amazon's data to your own. Mapping each ASIN to your internal SKU and its landed cost is what makes profit-per-product reporting possible.
Amazon also uses an FNSKU to track your specific FBA units, which matters when inventory is lost or reimbursed. Watch for: ASINs that are not mapped to a SKU in your inventory system, because their sales and fees float around without a cost attached.
Example
Your 3-pack and 6-pack of the same candle have separate ASINs, which lets you see that the 6-pack earns a higher contribution margin after FBA fees.