OEE Calculator
Overall Equipment Effectiveness is the single number that tells you how much good product a line actually makes versus what it could make at full speed with zero downtime and zero defects. Enter your production numbers below to get your OEE and, more usefully, which of the three factors is dragging it down.
Enter your production numbers
Your OEE
Your biggest loss is performance at 85.7%. Fix that before touching the others — chasing the smallest loss is the most common way OEE work gets misdirected.
Around the average for discrete manufacturing. Real, reachable gains sit between here and 85% if you attack the biggest loss first.
How OEE is calculated
OEE multiplies three factors, each a percentage between 0 and 100%. Because they multiply, a weak score on any one drags the whole result down — which is exactly why the calculator flags your lowest factor.
- Availability = Run time ÷ Planned production time. Run time is the planned time minus every stop, including changeovers.
- Performance = (Ideal cycle time × Total pieces) ÷ Run time. It captures speed losses — small stops and running below nameplate speed.
- Quality = Good pieces ÷ Total pieces. Count only first-pass good parts; reworked parts are a quality loss.
- OEE = Availability × Performance × Quality.
How to read your OEE score
Do not chase a single benchmark. The value is in the trend and in which factor is weakest, not the headline number. As rough reference points from total productive maintenance practice:
- 85% — the widely-cited "world-class" benchmark. Genuinely rare.
- ~60% — typical for discrete manufacturing.
- 40–65% — what most lines honestly score the first time they count every minute of planned time and only first-pass-good parts.
A high OEE on a first measurement almost always means the inputs were generous — usually a planned-time denominator that quietly excludes changeovers, or a cycle time set slower than the machine's real speed. An honest low number is more useful than a flattering high one, because it shows you where the capacity is hiding.
Worked example
The calculator loads with a realistic example: an 8-hour shift (480 minutes) with 60 minutes of stops, a 30-second ideal cycle time, 720 pieces produced and 690 good. That gives 87.5% Availability, 85.7% Performance and 95.8% Quality — an OEE of about 71.8%, with performance the biggest loss. Reset any time with the button, then swap in your own numbers.
Once you know your OEE and your biggest loss, the work is closing that gap. Our manufacturing optimization guide walks through how to attack the six big losses in the right order and make the gains stick, and choosing the right operations metrics covers what else belongs on the dashboard next to OEE.
OEE measures one line. If you want the wider read — whether the operation around that line is documented, visible, owned and improving — score it with our operations maturity assessment.