OEE Calculator

How it works

1. 1Enter planned production time and actual run time — the ratio gives Availability, capturing downtime losses.
2. 2Enter ideal cycle time (s/unit) and total units produced — compared against run time this gives Performance, capturing speed losses.
3. 3Enter good units alongside total units — the ratio gives Quality, capturing defect losses. OEE = Availability × Performance × Quality.

Use cases

• Benchmarking a production line against the world-class 85% OEE target to identify where losses occur.
• Comparing shift-by-shift or machine-by-machine OEE to prioritise maintenance and improvement projects.
• Reporting manufacturing KPIs to operations managers and continuous-improvement teams.

Frequently asked questions

What is a good OEE score?

World-class OEE is considered to be 85% or above. An OEE of 100% means you are producing only good parts, as fast as possible, with no downtime. Most manufacturers start between 40–60% and target 85%.

How is OEE calculated with an example?

With 480 min planned, 420 min run time, 30 s/unit ideal cycle, 800 units produced, and 780 good units: Availability = 420/480 = 87.5%, Performance = (30 × 800)/(420 × 60) = 95.2%, Quality = 780/800 = 97.5%. OEE = 87.5% × 95.2% × 97.5% ≈ 81.2%.

Why does this tool convert run time to seconds for the performance calculation?

Ideal cycle time is entered in seconds per unit, so run time must also be in seconds for the units to cancel correctly: Performance = (s/unit × units) ÷ s = dimensionless fraction. The tool multiplies run time (entered in minutes) by 60 internally.