OEE Calculator — Overall Equipment Effectiveness
Calculate Overall Equipment Effectiveness (OEE) from availability, performance, and quality metrics.
World Class
Formula
**OEE Formula**
OEE = Availability × Performance × Quality
Availability = (Planned Time − Downtime) ÷ Planned Time × 100
Performance = (Actual Output ÷ Max Theoretical Output) × 100
Quality = (Good Units ÷ Total Units Produced) × 100
Benchmarks: ≥85% World Class | 75-84% Excellent | 60-74% Typical | <60% Low
Worked Example
**Example:** 8h shift, 30 min downtime, 450/500 units, 445 good
Availability = (480−30)÷480 = 93.75%
Performance = 450÷500 = 90%
Quality = 445÷450 = 98.9%
OEE = 0.9375 × 0.90 × 0.989 = **83.4% (Excellent)**
Frequently Asked Questions
What is a good OEE score?
85% is world class. Most plants achieve 60-75%. Below 60% indicates significant improvement opportunities.
What causes low availability?
Equipment breakdowns, changeovers, and unplanned downtime. Preventive maintenance and SMED (setup reduction) are common countermeasures.
How is performance different from utilization?
Performance measures whether the machine runs at maximum speed when running. Utilization measures how much of planned time the machine is actually running.