What an Inventory Aging Report Actually Tells You

An inventory aging report sorts your stock by how long it's been on hand. It's a useful starting point — but age by itself can be misleading, and treating it as the whole picture leads to bad calls.

What age actually measures

Inventory age is typically measured as days since the product was received, or days since it last sold — these are different signals and it's worth being precise about which one a report is showing you. A product received 300 days ago that still sells steadily every week is not a problem. A product received 30 days ago that has never sold once might be, depending on the category.

Why age alone isn't enough

Two SKUs can have identical age and completely different urgency. A $4 item that's been sitting for 200 days ties up very little cash. A $400 item sitting for the same 200 days is a materially different problem. Age tells you how long something has been a candidate for action; it doesn't tell you how much is at stake or what to do about it.

What to pair it with

Cash tied up (quantity on hand × unit cost) — how much this specific SKU costs you to keep holding.
Sales velocity — whether it's still moving at all, and how fast.
Margin — how much room there is to discount before hitting cost.

Combining these into a single score is how you go from “this product is old” to “this product is old, ties up $600, still has 40% margin, and is a strong candidate for a 25% markdown” — an actual decision, not just a fact. See our guide on calculating dead stock for the cash-tied-up side of that math.

Using it as part of a regular process

An aging report is most useful as one input into a recurring inventory audit, not a one-time export you look at and set aside. Inventory Assassin combines age, cash tied up, sales velocity, and margin into a single prioritized list automatically, so you don't have to reconcile multiple reports by hand.