OEE Calculator
Calculate Overall Equipment Effectiveness from shift time, downtime, cycle time and piece counts, with TEEP and the six big losses broken out in minutes.
Time
Output
| Loss | Bucket | Minutes lost | Share of planned time |
|---|---|---|---|
| 1. Equipment failure / breakdowns | Availability | 32.0 | 7.6% |
| 2. Setup and adjustments | Availability | 15.0 | 3.6% |
| 3. Idling and minor stops | Performance | 25.0 | 6.0% |
| 4. Reduced speed | Performance | 26.8 | 6.4% |
| 5. Process defects | Quality | 5.0 | 1.2% |
| 6. Startup / yield rejects | Quality | 2.0 | 0.5% |
| Total loss | All six | 105.9 | 25.2% |
| Fully productive time | Value-adding | 314.1 | 74.79% |
60-85% is a typical, improvable line. The biggest single loss in the table below is usually where the fastest gain is.
A = run time ÷ planned production time · P = (ideal cycle time × total count) ÷ run time · Q = good count ÷ total count · OEE = A × P × Q · TEEP = OEE × utilisation
Worked example (the standard OEE reference case): a 480-minute shift with 60 minutes of breaks leaves 420 minutes planned; 47 minutes of downtime leaves 373 minutes of run time; 19,271 pieces at a 1.0-second ideal cycle with 423 rejects. Availability = 373 ÷ 420 = 88.81%, Performance = 19,271 ÷ (373 × 60) = 86.11%, Quality = 18,848 ÷ 19,271 = 97.80%, so OEE = 74.79% — matching the published figure.
The three factors multiply, so a line at 90% on each still only reaches 72.9% OEE — that multiplication is the whole point of the metric. The six-big-losses table converts every loss into minutes of planned production time so they can be compared directly; fully productive time plus the six losses equals planned production time by construction. TEEP additionally charges you for the hours the line was not scheduled at all. All calculations run locally in your browser and nothing is uploaded.
What is the OEE Calculator?
Overall Equipment Effectiveness is the standard measure of how much of your planned production time actually produced good parts at full speed.
- Availability, performance, quality and OEE from shift and count data
- Ideal cycle time entered in seconds, minutes or units per hour
- TEEP from calendar time so unscheduled hours are counted too
- Six big losses in minutes, adding up exactly to planned production time
- Performance capped at 100% with an explanation of what went wrong
- Warns when downtime exceeds the planned production time
How to use the OEE Calculator
- 1
Enter the shift length and the planned stops — breaks, meals and scheduled maintenance.
- 2
Add breakdown and setup minutes, plus the minutes lost to idling and minor stops.
- 3
Choose your cycle time unit and enter the ideal cycle time, total pieces and rejects.
- 4
Read availability, performance, quality and OEE in the stat tiles.
- 5
Use the six-big-losses table to see which loss is costing the most minutes.
About the OEE Calculator
Overall Equipment Effectiveness is the standard measure of how much of your planned production time actually produced good parts at full speed. It is the product of three factors: availability, performance and quality. Because they multiply, a line running at 90% on each still only reaches 72.9% OEE, which is exactly the point of the metric.
Enter the shift length, planned stops, breakdown and setup minutes, the ideal cycle time and your piece and reject counts. The calculator returns each factor, OEE, and TEEP once you add the calendar time the line was not scheduled at all. It also converts every loss into minutes of planned production time and maps them onto the six big losses.
Performance is capped at 100% with a warning, because a line beating its own ideal rate always means the ideal cycle time is understated. Everything is computed in your browser and nothing is uploaded. Estimates for planning, not engineering advice.
Frequently asked questions
How do you calculate OEE?
Availability is run time ÷ planned production time, performance is (ideal cycle time × total count) ÷ run time, and quality is good count ÷ total count. OEE is the three multiplied together. A 420-minute planned shift with 373 minutes of run time, 19,271 pieces at a one-second ideal cycle and 423 rejects gives 88.81% × 86.11% × 97.80% = 74.79%.
What is a good OEE score?
85% is generally treated as world-class for discrete manufacturing and very few lines hold it across a full shift. 60% is typical for a line that has been measured and improved, and 40% is common for one that has never been measured at all — usually with a large, cheap changeover win still available.
What is the difference between OEE and TEEP?
OEE measures how well you used the time you scheduled. TEEP multiplies OEE by utilisation — planned production time ÷ all calendar time — so it also charges you for the hours the line sat idle because nobody scheduled it. TEEP answers whether you need another machine or another shift.
Why is my performance above 100%?
It cannot be: the line cannot beat its own ideal rate. Either the ideal cycle time is understated — the true fastest sustainable rate is quicker than the figure entered — or the piece count covers a longer period than the run time does. The tool caps the figure at 100% and flags it.
What are the six big losses?
Breakdowns and setup or adjustments hit availability; idling with minor stops and reduced speed hit performance; process defects and startup rejects hit quality. Expressing all six in minutes of planned production time is what makes them comparable, and the table here does exactly that.
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