OEE & Factory Performance worked example

Unplanned Downtime Ratio at 3.6% target unplanned downtime ratio: a worked example

This worked example runs the unplanned downtime ratio numbers for a tougher week than the baseline: 3.6% target unplanned downtime ratio instead of the typical 5%. Calculate unplanned downtime ratio for OEE & Factory Performance: unplanned downtime as a share of total scheduled time.

The inputs for this scenario

  • Unplanned downtime minutes: 40 min (held at the documented default)
  • Total scheduled production minutes: 480 min (held at the documented default)
  • Target unplanned downtime ratio: 3.6 % (the input this scenario stresses; the baseline uses 5)

Working through the calculation

  • The calculation starts from the formula this tool documents: Unplanned downtime ratio = unplanned downtime ÷ total scheduled time × 100.
  • Unplanned downtime ratio works out to 8.33 % at these inputs, and this is the headline figure for the scenario.
  • Gap to target works out to -4.73 points at these inputs.
  • Unplanned downtime works out to 40 count at these inputs.
  • Total scheduled time works out to 480 count at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where target unplanned downtime ratio sits at 5% and the headline result is 8.33 %, this scenario lands almost exactly on the baseline at 8.33 %.
  • Use it in reliability reviews and OEE deep-dives to quantify breakdown losses and track whether maintenance improvements are moving the number. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Unplanned downtime ratio: 8.33 % (headline result)
  • Gap to target: -4.73 points
  • Unplanned downtime: 40 count
  • Total scheduled time: 480 count

Run it with your numbers

  • To rerun this with your own numbers, open the live Unplanned Downtime Ratio calculator, set target unplanned downtime ratio to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.