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OEE Calculator

Enter your shift data and get an instant OEE score with a full Availability, Performance and Quality breakdown — plus the financial cost of your losses.

Updated April 2026 Formula and benchmarks aligned with current industry standards

What is OEE and how is it calculated?

OEE (Overall Equipment Effectiveness) is the standard measure of manufacturing productivity. It is calculated by multiplying three factors: Availability (actual run time ÷ planned run time), Performance (actual output rate ÷ ideal output rate), and Quality (good units ÷ total units produced). The formula is OEE = Availability × Performance × Quality. A score of 85% is considered world-class. Most manufacturing sites average 60–65%. A line running at 90% Availability, 95% Performance and 98% Quality achieves 83.8% OEE — because all three factors compound. The biggest practical value of OEE is not the overall score but identifying which of the three components is dragging performance down so improvement effort goes to the right place.

85%
World-class OEE benchmark
60–65%
Typical manufacturing average
3
Components: A × P × Q
~35%
Typical output lost at avg OEE
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OEE Calculator & Shift Diagnosis

Availability — Time
hrs
hrs
Planned minus all downtime
Performance — Speed
min
Ideal time per unit at rated speed
All units including rejects
Quality — Output
£
OEE Score
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How OEE works — and what the numbers really mean

OEE is the most widely used manufacturing KPI for a reason — it captures time, speed and quality losses in a single number. But most sites misread it. Here's how to calculate it correctly and, more importantly, how to use it to drive real improvement.

OEE multiplies three independent loss measures together. Each one captures a different category of waste, and together they tell you the full story of where your planned production time actually went.

Availability

Actual run time divided by planned run time. Captures all time the line was stopped when it should have been running — breakdowns, changeovers, material shortages, and operator-related stops.

Performance

Actual output rate as a percentage of the ideal rate. Captures speed losses — minor stops and jams (often not recorded), reduced speed running, and operator pacing below rated capacity.

Quality

Good units as a percentage of total units produced. Captures all quality losses — rejects, rework, start-up scrap, and any product that doesn't pass first-time. Rework counts as a loss even if it's eventually sold.

Worked example — 8-hour shift
Planned run time8 hrs (480 min)
Actual run time (after 90 min downtime)6.5 hrs (390 min)
Availability (390 ÷ 480)81.3%
Units produced at 2 min ideal cycle time162 units
Performance (162 × 2 ÷ 390)83.1%
Good units / Total units (150 ÷ 162)92.6%
OEE (81.3% × 83.1% × 92.6%)62.6%

Notice how three components that each look reasonable individually compound to produce a significantly lower OEE. This is the multiplicative effect — and why all three pillars must be addressed simultaneously to reach world-class performance.

The most counterintuitive thing about OEE is how small improvements compound into large gains. Because Availability, Performance and Quality are multiplied together, improving each one by a small amount produces a disproportionately larger OEE improvement.

Compounding improvement — starting at 62.6% OEE
Baseline: 81.3% × 83.1% × 92.6%62.6%
Improve Availability by 5% → 85.3%65.7% (+3.1%)
Also improve Performance by 5% → 87.2%68.9% (+6.3%)
Also improve Quality by 2% → 94.5%70.2% (+7.6%)

The reverse is also true — a single weak component drags the entire result down. A line with 95% Availability and 97% Performance but only 75% Quality scores just 69.3% OEE. Quality is the bottleneck and no amount of uptime improvement will fix it.

Practical implication: always identify your weakest component first using the calculator above, then focus all improvement effort there before moving on. Spreading effort across all three simultaneously is less efficient than fixing the biggest loss first.

Food manufacturing has specific OEE challenges that differ from discrete manufacturing. High-care environments, allergen changeovers, CIP cycles, and variable raw material quality all create losses that other industries don't face at the same scale.

Availability losses

Changeover and CIP time typically dominate. On multi-SKU lines, changeovers can consume 20–30% of planned time. SMED analysis often reveals 40–50% of changeover time is internal work that could be externalised.

Performance losses

Minor stops from product jams, label misfeeds, and fill weight checks are often invisible — operators restart in under 2 minutes and don't record them. Accumulate to hours per week across a production floor.

Quality losses

Start-up waste during line stabilisation and fill weight rejects are the largest quality losses. A line producing 600 units/hour at 4% start-up reject rate wastes 24 units every startup — at scale, this is significant.

The most effective starting point on any food line is a downtime Pareto — categorising every stop by reason and duration over a 4-week period. In most sites, the top 3 stop reasons account for 60–75% of all downtime. Fixing those three fixes most of the Availability problem.

What is a good OEE score?
85% is the widely cited world-class benchmark. However, context matters. A high-speed single-product line should target 85%+. A multi-SKU food line with frequent allergen changeovers may typically run at 55–70% and still be performing well for its operating model. Your own trend over time is a more useful benchmark than an industry number.
What is the difference between OEE and TEEP?
OEE measures effectiveness during planned production time only. TEEP (Total Effective Equipment Performance) measures effectiveness against all calendar time. A line running one 8-hour shift per day with 85% OEE has a TEEP of roughly 28%. OEE is the right metric for operational improvement. TEEP is useful for capital investment decisions — it shows how much capacity exists in unscheduled time.
Should I measure OEE per line or per site?
Always per line first. Site-level OEE averages your best and worst performers and hides where the real losses sit. A site average of 72% might conceal a flagship line at 88% and a problem line at 54%. The 54% line is where the intervention belongs. Site-level OEE is useful for reporting trends upward, not for driving improvement decisions.
Why does my OEE look low even when the line looks busy?
The most common cause is Performance losses — specifically minor stops that operators restart quickly without recording. The line looks busy because it's running most of the time, but dozens of 1–2 minute stops per shift accumulate to significant lost output. Installing automatic counter resets or running a dedicated minor-stop observation study for one shift usually reveals the true scale of the problem.
How do I calculate OEE if I don't know my ideal cycle time?
The ideal cycle time should be based on the theoretical maximum speed of the equipment at its design capacity — not average observed speed. Check the equipment manufacturer's specification for rated throughput, then convert to time per unit. If no spec is available, use the best sustained performance observed over a full shift (not a short burst) as a proxy. Using average speed inflates Performance and produces a misleadingly high OEE.
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