What is a SKU in reselling?
Also: Stock Keeping Unit
A SKU (Stock Keeping Unit) is a unique identifier a reseller assigns to each inventory item to track it across storage, listings, and marketplaces. It ties a physical item to its photos, measurements, condition grade, and location, so nothing gets lost in a large inventory. SKUs make cross-listing and reconciliation possible at scale.
How it's used in a listing
A reseller who writes “SKU A-142” on a poly mailer is matching the shipped item to its inventory record so they know exactly what sold.
How it maps to the grade scale
A SKU isn't a condition grade, but it's the anchor a grade attaches to: GradeThread's 1.0–10.0 grade, photos, and flaw report all live against an item's SKU, keeping condition data linked to the right physical piece across every marketplace.
See where every condition sits on the GradeThread condition grading scale.
SKU — frequently asked
- Do resellers need SKUs?
- Once inventory grows past a few dozen items, yes. A SKU uniquely identifies each item so you can find it, match a sold order to the right piece, and keep its photos, measurements, and condition grade attached. Small sellers may skip them.
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