OEE Calculator: Availability, Performance, and Quality
Calculate overall equipment effectiveness (OEE) from planned production time, downtime, ideal cycle time, total count, and good count. The calculator reports Availability, Performance, Quality, and their combined OEE percentage. If Performance exceeds 100%, it flags the result for review.
OEE is only useful when the time window and loss definitions are consistent. It is a measure that can help reveal production losses; it does not identify their causes by itself.
Interactive calculator
Enter values and select Calculate.
The three OEE factors
Run time is planned production time minus downtime. Availability is run time ÷ planned production time. Performance is ideal cycle time × total count ÷ run time. Quality is good count ÷ total count. OEE is Availability × Performance × Quality.
Enter time in minutes and ideal cycle in seconds per part. The calculator converts minutes to seconds for the Performance calculation. Exclude schedule loss, such as planned breaks when production was not expected, before entering planned production time. Include the stop time that your OEE rules classify as downtime.
Worked example
For 420 planned minutes, 47 minutes of downtime, an ideal cycle of 1 second, 19,271 total parts, and 18,848 good parts, run time is 373 minutes. Availability is 88.81%, Performance is 86.11%, Quality is 97.80%, and OEE is about 74.79%.
These values align with the worked example and definitions in Vorne’s OEE calculation guide. OEE can also be expressed as good count × ideal cycle time ÷ planned production time, but the three-factor calculation exposes more information about the loss categories.
Interpret the result carefully
If Performance is above 100%, check the ideal cycle time, unit conversions, count, and time window. A value above 100% usually indicates that the entered ideal cycle does not represent the fastest achievable cycle or that the data definitions do not match.
Comparisons can mislead when one shift includes changeovers and another excludes them, or when reworked parts count as good in one report but not another. Set a clear threshold for recording short stops and apply it consistently. Pair the OEE factors with reason codes, process observations, and quality data to decide what to investigate.
For the related pace required to meet demand, use the takt time calculator. Do not treat an OEE value as an industry rating or a complete measure of business performance.
