Overall Equipment Effectiveness (OEE)
Overall Equipment Effectiveness (OEE) is a manufacturing metric that measures how well equipment performs compared to its ideal. It combines availability (uptime versus downtime), performance (actual speed versus maximum speed), and quality (share of good parts) to show what percentage of planned production time is truly productive.
OEE is calculated by multiplying the three factors: availability x performance x quality. A score of 100 percent means the equipment produced only good parts, as fast as possible, with no unplanned stops.
Equipment health monitoring (EHM) is not part of the OEE calculation, but it improves all three factors. For availability, spotting potential issues early lets teams schedule maintenance before breakdowns, reducing unplanned downtime. For performance, detecting degradation early allows adjustments that keep production speed near maximum. For quality, catching equipment problems early helps prevent defective products and raises the percentage of good parts.
OEE is often confused with simple uptime or utilization. Uptime only reflects availability, while OEE also accounts for slow cycles and defective output, so a machine can run all shift and still have a low OEE.