Harpy Glossary

OH (On-hand Inventory)

Amazon & D2C glossary · Harpy Media

OH (On-Hand Inventory) is the quantity of sellable stock physically sitting in a warehouse and available to fulfil an order right now. It excludes everything else that appears in an inventory ledger: incoming shipments still in transit, units reserved against pending orders, and anything damaged or flagged unsellable.

What is OH?

The definition is narrow on purpose. On-hand is the number that decides whether today’s order can ship — and the distinction between on-hand and total inventory is where some of the most expensive operational mistakes begin, because a full ledger and an empty shelf are not the same thing.

Why on-hand drives algorithmic visibility

Search systems want to show shoppers products that can actually be bought and delivered. Availability that dips to zero interrupts the sales history that supports a listing’s ranking; availability that swings wildly undermines the delivery promises and conversion signals built into that ranking. Stable, sufficient on-hand is what lets a listing compete.

At the other end, too much on-hand carries its own cost: storage fees, aged-inventory surcharges, and a hit to inventory-performance scores that can restrict how much stock you are allowed to send in. The operational target is neither maximum nor minimum but rhythm — enough cover to protect availability, not so much that dead stock accumulates.

Managing it as a live number

The working formula subtracts everything unavailable from everything received: total units received, minus units sold, minus units reserved, minus unsellable units. What remains is the quantity you can actually sell today — and it should be consulted before any decision that assumes stock: advertising pushes, promotions, and replenishment timing.

The setting around it is a pair of thresholds: a safety level below which a reorder triggers, and a target cover level that keeps availability comfortable without inviting storage penalties. Both should be set from measured velocity and real lead times, not from optimism — and reviewed as product performance changes, because a threshold that was correct in spring is rarely still right in the fourth quarter.

OH = Total Units Received − (Units Sold + Units Reserved + Unsellable Units)The result is the maximum number of transactions that can be served immediately. Incoming shipments and reserved or damaged units do not count, however visible they look in the ledger.

In practice

A private label seller forecast daily velocity of 30 units and sets a 45-day on-hand target — around 1,350 units — inside the fulfilment network. Automated supply-chain tooling triggers the next factory purchase order when live on-hand dips below 600 units, timed against a lead time that includes freight and receiving. The listing never runs dry, inventory performance stays strong, and no aged stock accumulates on the other side.

⚠️ Watch out. A competing seller reads “receiving” status on 2,000 units as though it were stock and switches on an aggressive daily advertising push. But the pallets are still on a trailer in the yard: sellable on-hand is zero. The campaign pays for impressions that cannot convert, the conversion data that the ranking systems read is damaged during exactly the period it mattered, and the money spent bought nothing but a lesson in the difference between inbound and on-hand.

💡 Harpy tip. Make on-hand the line you look at before spending anything. Before a promotion, an advertising push, or a replenishment decision, check the sellable figure — not the ledger total — and check it per SKU, not in aggregate, because an account can be comfortably stocked overall and empty on the one product being advertised.

How Harpy Media helps

Inventory health is a weekly instrument in our account routines: sellable on-hand tracked per SKU, reorder points set against measured lead times, and availability checked before any promotional spend is committed.

OH FAQ

What is the difference between on-hand and available inventory?

They are closely related: on-hand counts sellable units physically present, and available reflects what can be committed to orders at that moment. The practical point is the same — units that are incoming, reserved, or damaged do not count as sellable, however the ledger displays them.

Why does on-hand inventory affect my IPI score?

Because inventory performance scoring reads the health of your stock position: availability without excess. Too little stock risks stockouts that interrupt sales history; too much sits past its useful life, incurring storage costs and signalling overstock. Both directions pull the score down.

How much on-hand inventory should I hold?

Enough to cover measured sales velocity across the replenishment lead time, plus a safety margin for forecast error and transit variance. The number is product-specific: it depends on how fast the item sells, how long a restock really takes, and how volatile that lane is.

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