Question
Why use months without sales as an input?
Because time without movement is one of the clearest signals that inventory may have become stale enough to require action.
Ecommerce
Use OmniCalc's dead stock calculator to estimate how much cash is trapped in unsold inventory that has stopped moving.
Dead stock calculator
Use unsold units, unit cost, and months without sales to estimate inventory value at risk and flag stock that may already be dead.
Why this result matters
An ecommerce inventory-risk calculator for estimating the capital tied up in unsold inventory that has gone without sales for months. Use the tool above to enter a few clear inputs and get a practical answer you can use right away.
This dead stock calculator helps ecommerce operators estimate how much working capital is trapped in inventory that has gone stale. It is useful because dead stock does more than occupy shelf space — it also ties up cash that could have been used on faster-moving products or healthier inventory turns.
Formula and method
The calculator estimates dead-stock exposure by multiplying unsold units by unit cost to find the value at risk, then spreading that value across the months without sales to show how long the capital has remained trapped. It also flags inventory that has sat without sales long enough to likely qualify as dead stock.
Example
If 480 units remain unsold, each unit cost $11.50, and the product has gone 4 months without sales, the calculator estimates the capital tied up and flags the inventory as likely dead stock.
FAQ
Short answers to the questions people often ask before or after using the tool.
Question
Because time without movement is one of the clearest signals that inventory may have become stale enough to require action.
Question
No. It is a practical indicator, not a final accounting rule. Seasonality, product lifecycle, and replenishment strategy still matter.
Question
Use it to prioritize markdowns, bundling, liquidation, or supplier changes before more cash stays trapped in the SKU.
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