OEE Calculator — OEE Formula, OEE Calculation & World-Class Benchmark (Free)
Free OEE calculator: enter planned time, downtime, ideal cycle time, total output, and good units — get Availability %, Performance %, Quality %, and OEE % instantly, with a benchmark against world-class 85%. No signup required.
Calculator
No signup required. Results are indicative—verify for your standards.
Availability
87.5%
target >90%
Performance
83.3%
target >95%
Quality
94.3%
target >99%
OEE
68.8%
Typical — room to improve
World-class = 85% · Average = 60%
Formula
OEE = Availability × Performance × Quality. Availability = (Planned time − Downtime) ÷ Planned time. Performance = (Ideal cycle time × Actual output) ÷ Run time. Quality = Good units ÷ Total units produced. All three factors are expressed as decimals (0–1) then multiplied; the result is converted to a percentage.
Example calculation
Planned 480 min, downtime 60 min, ideal cycle 1 min/unit, actual output 350 units, good units 330. Availability = (480−60)÷480 = 87.5% Performance = (1×350)÷420 = 83.3% Quality = 330÷350 = 94.3% OEE = 87.5% × 83.3% × 94.3% = 68.8% This line is below the 85% world-class target. Biggest loss is Performance — investigate micro-stops and speed losses first.
Engineering notes
World-class OEE: 85%+. Industry average: 60%. Most new plants start at 40–50%. The six big losses and which OEE factor they affect: • Equipment breakdown → Availability • Setup & changeover → Availability • Minor stoppages (< 5 min) → Performance • Reduced speed → Performance • Process defects → Quality • Startup rejects → Quality Address the biggest loss first. In most plants this is Performance (micro-stops and speed losses) which are rarely logged but cumulatively steal 5–15% of shift time.
When to use this calculator
- TPM baseline — measure current OEE before starting Total Productive Maintenance to track improvement
- Capacity analysis — find true available capacity before committing new orders or buying equipment
- Shift comparison — identify which shift or operator achieves the best OEE and replicate their practices
- Maintenance ROI — prove that preventive maintenance investment is improving Availability over time
- Capital expenditure avoidance — demonstrate existing capacity is sufficient after OEE improvement instead of buying new machines
Frequently asked questions
- What is a good OEE score?
- OEE 85%+ is world-class. 60–85% is typical for manufacturers with active improvement programmes. Below 60% is common in plants without structured maintenance. For individual components: world-class Availability >90%, Performance >95%, Quality >99.9%. Most plants suffer most in Performance (speed losses) followed by Availability (breakdowns and changeovers).
- How do you calculate OEE step by step?
- Step 1: Availability = (Planned time − Downtime) ÷ Planned time. Step 2: Performance = (Ideal cycle time × Total units produced) ÷ Run time. Step 3: Quality = Good units ÷ Total units produced. Step 4: OEE = Availability × Performance × Quality. Example: 87.5% × 83.3% × 94.3% = 68.8%.
- What are the six big losses in OEE?
- Availability losses: (1) Equipment failure/breakdown, (2) Setup and adjustment time. Performance losses: (3) Minor stoppages and idling (< 5 min), (4) Reduced speed below rated rate. Quality losses: (5) Process defects and rework during normal production, (6) Startup rejects during warm-up. TPM targets all six with separate countermeasures: PM for breakdowns, SMED for changeover, autonomous maintenance for minor stoppages.
- Should I use planned production time or total calendar time?
- Use planned production time (scheduled shift hours minus meals, planned breaks, and planned PM outside shift). This is the standard OEE definition and isolates equipment performance from scheduling decisions. If you also want to measure scheduling efficiency, calculate TEEP = OEE × Utilisation, where Utilisation = Planned time ÷ Calendar time. TEEP is always lower than OEE.
- What does OEE Performance measure?
- Performance captures speed losses — the gap between how fast the machine actually ran versus its rated maximum speed. Performance = (Ideal cycle time × Total output) ÷ Run time. Causes of low Performance include micro-stoppages (< 5 min, typically unlogged), worn tooling, operator speed adjustments, and upstream feed restrictions. Performance below 90% almost always means micro-stops are being missed in the maintenance log.
- How do I use OEE to find the biggest improvement opportunity?
- Calculate Availability, Performance, and Quality separately. The lowest factor is your biggest loss and first priority. If Availability is 70%, focus on breakdown reduction and SMED. If Performance is 80%, investigate micro-stops and speed losses. If Quality is below 95%, run a Pareto on defect types — typically 2–3 root causes produce 80% of scrap. Fix the largest loss before moving to the next.
Related calculators
Looking for industrial vendors in India?
Post your procurement requirement free on the CI Suite Pro marketplace. Engineering, AMC, logistics, civil, IT — receive proposals from verified vendors within 24 hours.