What is stock runway (days of cover)?

Stock runway, also called days of cover, is the number of days a product's current stock will last if it keeps selling at its recent pace.

How to calculate it

Stock runway = units in stock ÷ average daily sales

Average daily sales is units sold over a recent period divided by the number of days. A 30-day window is a common choice: long enough to smooth out odd days, short enough to reflect what's selling now.

Core WooCommerce doesn't forecast sell-out dates. Analytics › Stock lists products by stock status (In stock, Low stock, Out of stock, On backorder), but "low stock" is a fixed number, not a measure of time. To get runway yourself, take Items sold from Analytics › Products for the last 30 days and the current stock from Analytics › Stock, then divide. Askshelf's stock-runway lookup does this for products and variations that will run out within a set number of days.

A worked example

Say you have 45 units of a hoodie and sold 90 in the last 30 days, so 3 a day.

• Stock runway: 45 ÷ 3 = 15 days

A second product with 45 units that sells 1 a week has a runway of more than 300 days. Both might show as "In stock".

Why it matters

Runway turns a stock count into a deadline. Compare it with your supplier's lead time: if runway is shorter than lead time, you'll run out before a new order arrives. Very long runways point the other way, toward dead stock. See how to find products about to sell out and WooCommerce inventory forecasting.