OEE and TEEP – how to calculate machine efficiency with examples
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OEE (Overall Equipment Effectiveness) shows how effectively planned production time is utilized. You calculate the value by multiplying availability, performance, and the ratio of good products. The important part is not just the total figure, but which losses are hidden behind it.
What is the difference between OEE and TAK?
OEE is the international term. TAK is often used as the Swedish abbreviation for Availability, Performance, and Quality. Terms and local measurement definitions can vary between companies. Therefore, write down how you define each factor before using the figures for follow-up.
How to calculate OEE – formulas and examples
| Factor | Calculation | Example |
|---|---|---|
| Availability | Operating time / planned production time | 405 / 450 = 90% |
| Performance | Ideal time per unit × total quantity / operating time | 95% |
| Quality | Good quantity / total quantity | 98% |
| OEE | 0.90 × 0.95 × 0.98 | 83.79% |
The example is illustrative. If you measure performance in minutes, cycle time and operating time must use the same unit of time. Record whether scrap and rework should be treated as a quality loss and avoid counting the same loss twice.
What data is needed in an OEE register?
- Planned production time: the time interval during which the machine is expected to produce, with documented handling of breaks and planned interruptions.
- Downtime: start, end, duration, and cause, for example, breakdown, material shortage, or changeover.
- Quantity and ideal time: total quantity, product variant, and correct cycle time.
- Good parts: scrap, rework, and approved quantity.
- Responsibility and follow-up: date, shift, machine, comments, and decided actions.
Checklist for starting measurements on the workshop floor
- Select a limited machine or production cell.
- Define planned time and categories for downtime.
- Verify a reasonable ideal time for each product.
- Collect a representative baseline over several shifts.
- Rank the largest losses and appoint persons responsible for actions.
- Follow the same measurement definition after improvements have been made.
Common mistakes in OEE follow-up
The most common mistake is to follow the total figure without identifying the causes of loss. Other errors include stating the wrong ideal cycle time, counting stops differently between shifts, or making OEE a metric for individual employees. OEE works best as a tool for process improvement, not as an isolated performance rating.
Frequently asked questions
Is higher OEE always better?
Not necessarily. High OEE on the wrong product, overproduction, or growing intermediate stocks can still create unnecessary costs. Evaluate the metric in conjunction with delivery precision, capacity, and quality.
How is changeover time handled?
If the changeover occurs during the defined planned production time, it is normally counted as an availability loss. Document your measurement principle consistently.
Can I calculate OEE in Excel?
Yes, for a limited process, a consistent register with production data, planned time, downtime, and quality outcomes is often sufficient.
Deepen your knowledge in the same area
- Overview: Production control and quality management
- Material Requirements Planning in practice
- FMEA – prevent errors before they occur
- 8D – investigate recurring quality problems
Sources and further reading
Last updated: October 9, 2026. The guide provides general practical guidance and should be adapted to your own operations.
