Leather, Footwear & Accessories Manufacturing worked example

Supplier Lead Time Buffer with material inventory on hand of 75 units: a worked example in leather, footwear & accessories manufacturing

What does the result look like when material inventory on hand reaches 75 units? The full calculation is worked below with real intermediate numbers. Use this when setting safety stock levels for leather hides, outsoles, insoles, hardware, or zippers. Also useful after a supplier changes lead time, when onboarding a new tannery, or when building inventory ahead of peak season production.

The inputs for this scenario

  • Material inventory on hand: 75 units (raised for this scenario; the documented default is 30)
  • Daily material consumption: 21 units / day (unchanged)
  • Supplier safety factor: 120 units (unchanged)

Working through the calculation

  • Applying the documented formula (Cycle stock = daily material consumption x supplier lead time) to the inputs above produces each figure below.
  • At this operating point the engine returns 0.03 days for protected days of supply, the number this scenario is built around.
  • At this operating point the engine returns 3.57 days for unprotected days.
  • At this operating point the engine returns 75 pieces for inventory.
  • At this operating point the engine returns 21 pieces / day for daily usage.

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 150% above the baseline at 0.03 days.
  • A figure at this level is achievable when material inventory on hand is genuinely sustained, not just peaked for a shift. It assumes steady daily consumption; seasonal production spikes or a sudden large order will burn through coverage faster than the figure implies.

Results at a glance

  • Protected days of supply: 0.03 days (headline result)
  • Unprotected days: 3.57 days
  • Inventory: 75 pieces
  • Daily usage: 21 pieces / day

Run it with your numbers

  • Every input above is editable in the live Supplier Lead Time Buffer calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.