Supply Chain & Procurement worked example

Vendor Managed Inventory Days with on-hand stock at the vmi bin of 11,300 units: a worked example

This scenario runs the vendor managed inventory days calculation on the strong side: on-hand stock at the vmi bin of 11,300 units, with every other input held at its documented default. Use it when vendor managed inventory days in supply chain and procurement is being sized for a buffer or safety stock review.

The inputs for this scenario

  • On-hand stock at the VMI bin: 11,300 units (raised for this scenario; the documented default is 4,500)
  • Average daily consumption: 300 units / day (unchanged)
  • Buffer safety multiplier: 1.2 x (unchanged)

Working through the calculation

  • Applying the documented formula (Protected days = inventory on hand ÷ daily usage ÷ safety multiplier) to the inputs above produces each figure below.
  • At this operating point the engine returns 31.39 days for protected days of supply, the number this scenario is built around.
  • At this operating point the engine returns 37.67 days for unprotected days.
  • At this operating point the engine returns 11,300 pieces for inventory.
  • At this operating point the engine returns 300 pieces / day for daily usage.

How this compares with the baseline

  • Against the tool's baseline example, where on-hand stock at the vmi bin sits at 4,500 units and the headline result is 12.5 days, this scenario comes in 151% above the baseline at 31.39 days.
  • Use it on VMI bin walks and replenishment reviews to decide whether a top-up is needed before the next supplier visit. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Protected days of supply: 31.39 days (headline result)
  • Unprotected days: 37.67 days
  • Inventory: 11,300 pieces
  • Daily usage: 300 pieces / day

Run it with your numbers

  • Every input above is editable in the live Vendor Managed Inventory Days calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.