Glossary

OEE — Overall Equipment Effectiveness

OEE (Overall Equipment Effectiveness) is the gold-standard KPI for measuring manufacturing productivity. It captures how effectively a production asset is used compared to its full potential.

OEE = Availability × Performance × Quality

The OEE Formula

OEE = Availability × Performance × Quality
Availability = (Planned Production Time − Downtime) ÷ Planned Production Time
Performance = (Ideal Cycle Time × Total Pieces Produced) ÷ Run Time
Quality = Good Pieces ÷ Total Pieces Produced

Each component is expressed as a decimal (0.00–1.00) or percentage. A machine with 90% Availability, 95% Performance, and 98% Quality has an OEE of: 0.90 × 0.95 × 0.98 = 83.8%.

What Each OEE Component Measures

Availability measures time losses — unplanned downtime, planned maintenance, changeovers, and machine faults. A machine with 100% availability ran for its entire scheduled production time without stopping.

Performance measures speed losses — micro-stops, reduced speed operation, and cycle time deviations. A machine at 100% Performance ran at its designed ideal cycle time for every cycle it completed.

Quality measures defect losses — scrap parts, rework required, and startup rejects. A machine at 100% Quality produced only conforming parts on the first pass.

OEE Benchmarks

OEE ScoreClassificationTypical Context
Below 65%⚠️ PoorSignificant improvement opportunity. Common in plants without real-time monitoring.
65–75%📊 AverageTypical for plants using manual reporting.
75–85%✅ GoodWell-managed production lines with active improvement programs.
85%+🏆 World-classLean manufacturing benchmark (ISO 22400). Achieved with real-time monitoring and proactive maintenance.

The Six Big Losses

The Six Big Losses framework, originating from Total Productive Maintenance (TPM), maps every OEE loss to one of six categories:

Measure OEE in Real Time → Shopfloor Copilot calculates OEE automatically from OPC UA machine data — no manual entry.

See OEE Monitoring →

Frequently Asked Questions

What does OEE stand for?

OEE stands for Overall Equipment Effectiveness — a composite KPI measuring how effectively a manufacturing asset is used relative to its full potential. OEE = Availability × Performance × Quality. 100% OEE means the machine ran all planned time at full speed with zero defects.

What is a good OEE score?

World-class OEE is 85% or above. Average for discrete manufacturing is 65–75%. Below 65% indicates significant improvement opportunity. Process industries typically run 85–95%, batch manufacturing 60–75%.

How is OEE calculated?

OEE = Availability × Performance × Quality. Availability = (Planned Production Time − Downtime) ÷ Planned Production Time. Performance = (Ideal Cycle Time × Total Pieces) ÷ Run Time. Quality = Good Pieces ÷ Total Pieces.

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