OEE Formula — 5 Worked Examples from Real Manufacturing Plants

OEE (Overall Equipment Effectiveness) is calculated as Availability × Performance × Quality. The formula is simple, but most plants get it wrong on small details that change the final result by 10+ percentage points.

This guide presents 5 fully worked examples from real plant data, anonymized but otherwise unchanged. Each example shows the math step-by-step and flags the pitfalls that cause inflated reported OEE.

The OEE formula (1-sentence answer)

OEE = Availability × Performance × Quality.

Where:

• Availability = Run Time ÷ Planned Production Time
• Performance = (Total Count × Ideal Cycle Time) ÷ Run Time
• Quality = Good Count ÷ Total Count

Example 1 — Packaging line (79.5% OEE)

5-line beverage packaging plant. Bottle filler, 8-hour shift.

• Shift: 480 min / Breaks: 30 min / Planned Production Time = 450 min
• Stops: breakdown 22 min + material 18 min + minor stops 7 min = 47 min
• Run Time = 450 – 47 = 403 min
• Availability = 403/450 = 89.6%
• Total parts: 18,135 / Ideal cycle: 1.2 sec / Theoretical max: 20,150
• Performance = 18,135/20,150 = 90.0%
• Good parts: 17,881 / Rejects: 254
• Quality = 17,881/18,135 = 98.6%

OEE = 0.896 × 0.900 × 0.986 = 79.5%

Example 2 — Automotive Tier-2 stamping (71.3% OEE)

Hydraulic press, automotive structural parts. 8-hour shift.

• Planned Production Time = 480 min (continuous shift, breaks counted as availability loss per Nakajima method)
• Stops: 96 min total (breakdowns 38 + die changeovers 42 + safety 16)
• Run Time = 384 min, Availability = 80.0%
• Ideal cycle: 30 sec / Total parts: 700 / Theoretical: 768
• Performance = 700/768 = 91.1%
• Good parts: 685 / Rejects: 15
• Quality = 685/700 = 97.9%

OEE = 0.800 × 0.911 × 0.979 = 71.3%

Example 3 — Pharma blister packaging (56% OEE)

Blister packaging line, regulated GMP environment.

• Planned Production Time = 420 min (60-min cleaning excluded)
• Stops: 92 min (changeover 35 + sensor 22 + microstops 35)
• Availability = 328/420 = 78.1%
• Performance = 73.6% (significant micro-stop losses)
• Quality = 97.4%

OEE = 0.781 × 0.736 × 0.974 = 56.0%

Pitfall flagged: the plant’s reported OEE was 72%. Direct-sensor measurement revealed 16 percentage points of “invisible” Performance losses, mostly micro-stops under 5 minutes that operators did not log.

Example 4 — F&B filler line (67% OEE)

Liquid filler, multi-SKU, 12-hour shift with high changeover frequency.

• Planned Production Time = 660 min
• Stops: 178 min (5 changeovers averaging 22 min + breakdowns 38 + jams 30)
• Availability = 73.0%
• Performance = 94.2% (high speed when running)
• Quality = 97.3%

OEE = 0.730 × 0.942 × 0.973 = 66.9%

Pitfall flagged: changeovers were initially treated as “planned” and excluded from Availability — the inflated OEE was 81%. The Nakajima method includes them.

Example 5 — Plastics extruder (73% OEE)

Continuous-flow extrusion line, single product, 24-hour operation.

• Planned Production Time = 1,440 min
• Stops: 130 min (1 unplanned stop 45 + planned PM 60 + start-up 25)
• Availability = 91.0%
• Performance = 84.6% (sustained underspeed)
• Quality = 95.1%

OEE = 0.910 × 0.846 × 0.951 = 73.2%

Pitfall flagged: ideal cycle time set to nameplate value, not demonstrated best. Recalibrating revealed Performance was actually 76%, lowering OEE to 65.9% — a 7-point correction.

Common pitfalls across the 5 examples

Three errors caused 8-16 points of OEE inflation across these plants:

1. Wrong ideal cycle time (Plant 5) — using nameplate instead of demonstrated best
2. Excluding changeovers (Plant 4) — treating them as planned not Availability loss
3. Missing micro-stops (Plant 3) — manual logs don’t capture stops under 5 min

If your reported OEE seems much higher than peer plants in your sector, audit these three potential sources first.

Watch: How TeepTrak Customers Transform OEE

Related guides

• Oee Explained Mid Market Guide
• Ideal Cycle Time Empirical Calibration
• Six Big Losses Pareto Analysis
• Oee Availability Improvement Tactics

Frequently Asked Questions

What is the OEE formula?

OEE = Availability × Performance × Quality. Availability = Run Time / Planned Production Time. Performance = (Total Count × Ideal Cycle Time) / Run Time. Quality = Good Count / Total Count.

Can OEE be over 100%?

No. OEE cannot exceed 100% if calculated correctly. Performance values above 100% indicate the ideal cycle time is set too slow (typically using nameplate instead of demonstrated best). Recalibrate using actual best demonstrated cycle.

Should changeover time count against OEE?

Yes, in the Nakajima/TPM method (most widely used). Changeover counts as Availability loss. Excluding changeover typically inflates reported OEE by 8-12 percentage points compared to the standard.

How accurate are manual OEE calculations?

Manual paper-based OEE calculations are typically 10-18 percentage points HIGHER than direct-sensor measurement on the same line, because manual tracking systematically misses micro-stops, speed losses, and restart waste.

What ideal cycle time should I use in the OEE formula?

Use the actual demonstrated best cycle, sustained for at least 1 hour, on your specific product. Do NOT use the equipment manufacturer’s nameplate value (typically 5-15% conservative) or historical average (which bakes in slowness).

Why does my pharma plant have lower OEE than discrete manufacturing?

Pharma OEE benchmarks are 10-15 points lower than discrete manufacturing because of mandatory cleaning cycles, validation requirements, and tighter quality specs. World-class pharma packaging is 76% (vs 85%+ for automotive). Always benchmark within your specific sub-industry.