Multi-Location Days of Supply Calculator

About this calculator

Days of supply (also called days of inventory on hand) tells you how many days your current stock will last before running out, given a rate of demand. For a business with several warehouses or stores, the useful number is often the combined figure — total on-hand inventory across all locations divided by total daily demand across all of them.

Looking at locations individually can be misleading: one site might look dangerously low while another is overstocked, when pooled together the network is fine, or vice versa. Supply chain planners, inventory managers, and retail operations teams track combined days of supply to decide when to trigger a network-wide reorder, spot systemic overstock or shortage risk, and plan transfers between locations before individual sites run out.