OEE calculator.
Drag or type one production period and see availability, performance and quality, the minutes each one lost, and where to look first.
Where OEE comes from.
One 480-minute shift, stepped down by each loss. What is left at the bottom, as a share of the top, is the OEE.
Before you trust the number.
Five inputs can't show everything. Three cases to check before a result goes on the board.
When a ratio breaks. Zero run time or zero output leaves a ratio undefined, so look at that period on its own. Performance above 100% means the ideal cycle, the count or the time basis is wrong; the calculator shows it rather than capping it.
Collecting the inputs. Record a shift on the OEE tracking sheet and each stop on the machine downtime log, or read what OEE is and how to use it.
Mixed products. When one period runs several products, add up ideal cycle time × units for each one and use that total in place of ideal cycle time × total units. Take each ideal cycle from a time study.
Questions, answered.
How do you calculate OEE?
Multiply availability, performance and quality. Availability is run time divided by planned production time, performance is ideal cycle time multiplied by total units and divided by run time, and quality is good units divided by total units. The same result comes from ideal cycle time multiplied by good units, divided by planned production time.
What is a good OEE score?
85% is often cited as world-class, but the useful comparison is with your own baseline for the same machine and product. A rising OEE on a stable definition matters more than any benchmark.
What counts as planned production time?
The time the machine was scheduled to run: shift length minus planned breaks and periods with no work scheduled. Changeovers and planned maintenance inside that time are stops, so they reduce availability.
Why is my performance over 100%?
The ideal cycle time is usually set slower than the machine can really run, or the count or the time basis does not match. Correct the ideal cycle with a time study rather than capping the result.
Is my data stored or sent anywhere?
No. The calculation runs in your browser, and this page loads no analytics or session recording.
Bring the calculation onto the floor.
Bulk records stops, cycles and rejects as the work happens, so OEE comes from the record instead of a spreadsheet.