Production calculator

OEE Calculator

Score how much of planned production time made good units, and see which of the three factors pulls the score down. You need planned minutes, downtime, the ideal cycle, and total and good counts.

What this calculator does

  • Availability, performance and quality against a target, with the run time and gap that separate a line from the OEE it wants.

Formula used

  • Run time = planned production time − downtime minutes
  • Availability = run time ÷ planned production time; quality = good count ÷ total count
  • Performance = ideal cycle seconds × total count ÷ (run time × 60)
  • OEE = availability × performance × quality, or ideal cycle × good count ÷ (planned minutes × 60)
  • Gap to target = OEE − target OEE

Inputs explained

  • Planned Production Time: Scheduled production minutes for the window, before any stops.
  • Downtime: Stopped minutes inside planned time, from the downtime log.
  • Ideal Cycle Time: Fastest sustained seconds per unit the line can hold.
  • Total Count: All units produced in the window, scrap included.
  • Good Count: First-pass good units in the same window as total count.
  • Target OEE: OEE the site expects this line or window to reach.

How to use the result

  • Best suited to end-of-shift OEE review at the board, choosing which loss factor to attack, checking a shift against the OEE target.
  • Counts give quality and performance at the line level, not per machine. Setups and changeovers count as downtime when they run inside planned time.

Current U.S. benchmarks

  • The U.S. has 21,668 machinery manufacturing establishments employing about 1,086,146 workers (Census County Business Patterns, 2023).

Common questions

  • What counts as planned production time? The minutes the line was scheduled to make product, with breaks and planned stops already excluded. Downtime is what the log shows inside that window: breakdowns, changeovers past their allowance and starvation the line caused.
  • Why can OEE be higher than the performance factor suggests? Quality multiplies in, not performance alone. A line running slowly but making every unit good can still post a low OEE; check which factor is smallest before blaming speed.
  • Is 85% a good OEE target? It is a common goal for discrete manufacturing and near the top of what many lines sustain. Set yours from your best repeatable week, then raise it as the largest loss closes.
  • What if good count exceeds total count? The two counts describe different windows or one is a data error. All results are blanked rather than scoring inconsistent counts, and the blocking note asks you to reconcile them.
  • What is a good overall equipment effectiveness (oee)? Typical Overall Equipment Effectiveness (OEE) runs 55-65% (% of planned production time); 70-80% is good, and 85%+ is world-class. Discrete manufacturing reference. Continuous process plants often run higher; job shops with heavy changeovers often run lower. Trend matters more than the absolute number.

Related guides

Last reviewed 2026-10-01.