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General Amazon

FNSKU (Fulfillment Network Stock Keeping Unit)

Amazon's internal barcode for FBA inventory that links a product to a specific seller's account. Prevents commingling of inventory between sellers.

What Is an FNSKU?

The FNSKU is a unique barcode Amazon assigns to your FBA inventory. It ties a specific unit to your seller account, ensuring that when a customer buys your product, they receive YOUR inventory - not another seller's potentially different-quality stock.

FNSKU vs UPC

A UPC identifies a product universally. An FNSKU identifies that product as belonging to your specific seller account. Using FNSKUs prevents commingling issues where Amazon might ship another seller's version of the same product to your buyer.

Related Terms

ASIN (Amazon Standard Identification Number)

A unique 10-character alphanumeric identifier assigned by Amazon to every product in its catalog. Starts with "B0" for most products.

FBA (Fulfillment by Amazon)

Amazon's fulfillment service where sellers ship products to Amazon warehouses, and Amazon handles storage, packing, shipping, customer service, and returns.

SKU (Stock Keeping Unit)

A unique identifier you assign to each product variant in your inventory. Used internally for tracking, unlike ASIN which is Amazon's identifier.

Track This in SellerLegend

FBA Storage & Shipment Tracking

Monitor FBA inventory across all fulfillment centers with detailed storage cost tracking and inbound shipment status. Track monthly storage fees, the Aged Inventory Surcharge (long-term storage), aged inventory and inbound shipments to avoid surprise costs, and see which fulfillment centers hold your stock.

Inventory Management & Forecasting

Prevent Amazon FBA stockouts and reduce excess inventory costs. Track sales velocity across multiple time periods, get a recommended purchase date, and get data-driven quantity recommendations to maintain optimal stock levels.

Want to track this metric continuously?

SellerLegend gives you a frequently-updated dashboard with all the Amazon metrics that matter.

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