CMMS, EAM & Spare Parts Management worked example

Spare Parts Fill Rate at 68% target parts fill rate: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop target parts fill rate to 68%, then walk the calculation through step by step. Measure spare parts fill rate by comparing parts requests filled from stock with total valid MRO parts requests.

The inputs for this scenario

  • parts requests filled immediately from stock: 1,280 count (held at the documented default)
  • valid spare parts requests: 1,450 count (held at the documented default)
  • target parts fill rate: 68 % (the input this scenario stresses; the baseline uses 95)

Working through the calculation

  • The calculation starts from the formula this tool documents: Spare Parts Fill Rate rate = parts requests filled immediately from stock ÷ valid spare parts requests × 100.
  • Spare Parts Fill Rate rate works out to 88.28 % at these inputs, and this is the headline figure for the scenario.
  • Spare Parts Fill Rate gap to target works out to -20.28 points at these inputs.
  • parts requests filled immediately from stock works out to 1,280 count at these inputs.
  • valid spare parts requests works out to 1,450 count at these inputs.

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 %.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to target parts fill rate, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. 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: -20.28 points
  • parts requests filled immediately from stock: 1,280 count
  • valid spare parts requests: 1,450 count

Run it with your numbers

  • To rerun this with your own numbers, open the live Spare Parts Fill Rate calculator, set target parts fill rate to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.