CMMS, EAM & Spare Parts Management worked example

Spare Parts Fill Rate at 99% target parts fill rate: a worked example

What does the result look like when target parts fill rate reaches 99%? The full calculation is worked below with real intermediate numbers. a maintenance or asset-management team needs to evaluate service level, reorder points, supplier performance, and storeroom stocking effectiveness for a MRO parts demand period

The inputs for this scenario

  • parts requests filled immediately from stock: 1,280 count (unchanged)
  • valid spare parts requests: 1,450 count (unchanged)
  • target parts fill rate: 99 % (raised for this scenario; the documented default is 95)

Working through the calculation

  • Applying the documented formula (Spare Parts Fill Rate rate = parts requests filled immediately from stock ÷ valid spare parts requests × 100) to the inputs above produces each figure below.
  • At this operating point the engine returns 88.28 % for spare parts fill rate rate, the number this scenario is built around.
  • At this operating point the engine returns 10.72 points for spare parts fill rate gap to target.
  • At this operating point the engine returns 1,280 count for parts requests filled immediately from stock.
  • At this operating point the engine returns 1,450 count for valid spare parts requests.

How this compares with the baseline

  • Against the tool's baseline example, where target parts fill rate sits at 95% and the headline result is 88.28 %, this scenario lands almost exactly on the baseline at 88.28 %.
  • A figure at this level is achievable when target parts fill rate is genuinely sustained, not just peaked for a shift. A high fill rate alone can mask overstocking; pair it with inventory turns and stockout-on-critical-parts data to judge whether the result is healthy or just expensive.

Results at a glance

  • Spare Parts Fill Rate rate: 88.28 % (headline result)
  • Spare Parts Fill Rate gap to target: 10.72 points
  • parts requests filled immediately from stock: 1,280 count
  • valid spare parts requests: 1,450 count

Run it with your numbers

  • Every input above is editable in the live Spare Parts Fill Rate calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.