Leather, Footwear & Accessories Manufacturing worked example

Supplier Lead Time Buffer with material inventory on hand of 15 units: a worked example in leather, footwear & accessories manufacturing

Suppose material inventory on hand falls to 15 units. This page works the full calculation at that level so you can see exactly which result moves and by how much. Calculate the required raw material buffer inventory (leather, soles, hardware, linings) to protect production against supplier lead time variability. Ensures the cutting room and assembly line do not stop due to late material deliveries.

The inputs for this scenario

  • Material inventory on hand: 15 units (the input this scenario stresses; the baseline uses 30)
  • Daily material consumption: 21 units / day (held at the documented default)
  • Supplier safety factor: 120 units (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Cycle stock = daily material consumption x supplier lead time.
  • Protected days of supply works out to 0.01 days at these inputs, and this is the headline figure for the scenario.
  • Unprotected days works out to 0.71 days at these inputs.
  • Inventory works out to 15 pieces at these inputs.
  • Daily usage works out to 21 pieces / day at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where material inventory on hand sits at 30 units and the headline result is 0.01 days, this scenario comes in 50% below the baseline at 0.01 days.
  • It compares material inventory on hand against daily consumption to express coverage as protected and unprotected days of supply relative to lead time. When the numbers land here, the stressed input is the lever to work; the walkthrough above shows exactly how much each output recovers as it climbs back toward the baseline.

Results at a glance

  • Protected days of supply: 0.01 days (headline result)
  • Unprotected days: 0.71 days
  • Inventory: 15 pieces
  • Daily usage: 21 pieces / day

Run it with your numbers

  • To rerun this with your own numbers, open the live Supplier Lead Time Buffer calculator, set material inventory on hand to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.