Manufacturing & production
OEE and production KPIs: measuring plant performance
How to calculate OEE (availability, performance, quality) with a worked example, plus the production KPIs plant managers should review every shift and week.
Overall equipment effectiveness (OEE) measures how much of a machine's or line's planned production time is truly productive. It multiplies three factors: availability (was it running?), performance (was it running at the right speed?) and quality (were the units good?). OEE gives plant managers one number that reveals where capacity is lost, and three sub-numbers that show why.
OEE = Availability × Performance × Quality
The three factors
| Factor | Formula | Losses it captures |
|---|---|---|
| Availability | Run time ÷ planned production time | Breakdowns, changeovers, material shortages |
| Performance | (Ideal cycle time × total count) ÷ run time | Slow running, minor stops |
| Quality | Good count ÷ total count | Scrap, rework, rejects |
Worked example
A packaging line runs one 8-hour shift (480 minutes), with no planned breaks counted.
- Planned production time: 480 minutes.
- Downtime: 48 minutes (a changeover and a jam). Run time = 432 minutes.
- Availability = 432 ÷ 480 = 90%.
- Ideal cycle time: 1 minute per unit. Total count: 380 units.
- Performance = (1 × 380) ÷ 432 = 88.0%.
- Good count: 361 units. Quality = 361 ÷ 380 = 95%.
- OEE = 0.90 × 0.880 × 0.95 ≈ 75.2%.
The biggest loss here is performance: the line ran slower than ideal. That points the team at minor stops and speed, not breakdowns.
Interpreting OEE
- Compare a line with itself over time, not with other plants or published benchmarks with different definitions.
- Look at the factor with the largest loss first.
- Combine OEE with downtime reason codes so improvement work is specific.
- Do not game it: excluding "planned" downtime that is really lost time makes OEE look better without improving anything.
Other production KPIs
| KPI | Formula | Use |
|---|---|---|
| Output vs. plan | Actual output ÷ planned output | Daily plan attainment |
| Schedule adherence | Jobs completed as scheduled ÷ jobs scheduled | Planning reliability |
| First-pass yield | Units good the first time ÷ units started | Quality at source |
| Scrap rate | Scrap quantity or value ÷ total production | Material losses |
| Labor productivity | Output ÷ labor hours | Workforce efficiency |
| Changeover time | Time from last good unit to first good unit | Flexibility |
| Mean time between failures | Run time ÷ number of breakdowns | Equipment reliability |
| Cost per unit | Total production cost ÷ good units | Cost competitiveness |
A shift and week review rhythm
- Start of shift (10 minutes): yesterday's output, scrap and downtime; today's plan and risks.
- End of shift: recorded output, scrap and downtime reasons complete.
- Weekly (plant management): OEE trend by line, top downtime reasons, scrap by product, actions from last week.
- Monthly: KPIs against targets with improvement projects reviewed.
Getting reliable data
OEE is only as good as the downtime and count data. Record stops with reasons as they happen, count good and rejected units at the end of each stage, and keep ideal cycle times realistic and documented. Manual tally sheets work as a start; recording through the production system makes the data timely and consistent (WIP tracking).
Where Cirquolus fits
Cirquolus Production management includes productivity, performance and cost monitoring with mobile, line and countertop processing. Business Compass KPI turns plant KPIs into scorecards with owners and readings, and the improvement portfolio supports DMAIC, Kaizen and FMEA projects on the biggest losses.
Frequently asked questions
What is OEE?
Overall equipment effectiveness: the share of planned production time that produces good units at ideal speed, calculated as availability × performance × quality.
What is a good OEE score?
It depends on the industry and how losses are defined. Track your own trend and focus on reducing the largest loss.
What is the difference between OEE and productivity?
OEE measures equipment effectiveness. Productivity usually measures output per labor hour or per input.
How do you improve OEE?
Find the biggest loss factor, record its reasons, and run focused improvement projects such as faster changeovers, preventive maintenance or quality at source.
Bring this workflow to a Cirquolus demo.
Show us your current process, companies and branches. We will map it to the modules you need and propose a realistic rollout.