--- title: "OEE above 100%? Why a reported OEE can't be right | Recurline" description: "An OEE over 100% means the inputs are wrong. Here are the common reasons a reported OEE fails the sniff test, from a plant manager's point of view." canonical: https://recurline.com/blog/oee-above-100-percent --- [Blog](https://recurline.com/blog) · Operations craft · For operations # OEE above 100%? Why a reported OEE can't be right The Recurline team · 26 Oct 2026 · 3 min read In short OEE cannot exceed 100%, so a higher figure means an input is wrong. The usual causes are an ideal speed set too low, planned time that excludes real stops, or counts that include rework. Check the three inputs before you trust the percentage. Contains illustrative examples TL;DR. OEE is a ratio of good output to the best the line could have done in planned time. It cannot be more than 100%. If your report says 104%, or even a suspiciously calm 92%, one of the inputs is wrong. Check three things first: the ideal speed, the planned time and the good count. ## What does OEE actually measure? OEE is availability times performance times quality. In plain words: how much of the planned time the line ran, how close to ideal speed it ran, and how much of the output was good. The maximum is 100%: every planned minute running at ideal speed with no defects. See the glossary entry on [OEE](https://recurline.com/glossary) for definitions. Because it is a product of three ratios, a mistake in any one passes straight through to the headline. ## Why would the figure ever go above 100%? Because one of the three ratios exceeds 1, and nothing in the spreadsheet stopped it. Illustrative example: a fictional line has an ideal speed recorded as 400 units a minute. A new operator finds it runs happily at 480. Performance becomes 120%, and OEE reports 108%. The machine did nothing wrong. The standard did. ## Is the ideal speed set too low? This is the most common cause. The ideal speed is often copied from an old datasheet, a commissioning test or a figure someone agreed years ago. Equipment improves, products change, and the number stays. Eventually the line outruns its own ideal. The fix is to reset the ideal to a defensible best rate, agreed by operations and engineering, and to record the date of the change. When you reset it, past OEE figures will fall. That is correct, and you should warn everyone beforehand. ## Is the planned time too short? If planned time excludes breaks, changeovers, cleaning and “expected” stops, availability looks excellent. Quietly removing stops that are not truly planned from the denominator is a very effective way to raise a score. Illustrative example: a line reports 94% availability because 90 minutes of daily “planned maintenance” are excluded, although the work routinely overruns and is booked after the fact. Genuinely planned stops can sit outside OEE; they show up in broader measures such as TEEP. Stops that are not truly planned cannot. Be strict about what counts as planned. Our post on changeovers explains one case: [changeovers vs real losses](https://recurline.com/blog/changeovers-vs-real-losses). ## Is output being counted twice? Good count errors are common. Two counters on the same line, one before and one after a rework loop. A product counted at filling and again at packing. A scan that triggers twice on a reject. A good-count that exceeds the theoretical maximum in the period is a clear sign. Compare the day’s good count with run time multiplied by ideal speed. If the first is bigger, something is off. Rework is a subtler version. If reworked units are counted as good both times, quality looks better than it is. ## Are the clocks and shifts aligned? If production counts come from one system and run time from another, small misalignments make odd results. A run that straddles midnight may be counted partly in one day and partly in another. Daily OEE swings of 20 points with no change on the floor often come from this. It is tedious and it is common. Check that both counts and times use the same shift boundaries and the same clock. ## What is a sensible sniff test? Before you trust a number, ask four questions. - Is it between 0 and 100? If not, stop. - Is it above about 90% on a packaging line? Look harder. - Does it move when something obviously changed, such as a long breakdown? - Would the operators recognise it? The fourth is the best. Operators know when a day was bad. If the report says 91% on the day the filler broke down twice, the report is wrong. ## What can you do about it? Treat the OEE figure as a prompt for questions, not a verdict. A trustworthy loss list, with minutes and money against each loss, is more useful than a perfect percentage. ## What to do on Monday - Calculate good count against run time multiplied by ideal speed for last week. - Check the date and source of each line’s ideal speed. - List every stop currently excluded as “planned” and challenge each one. - Compare reported OEE against what the shift leads believe. - Write down the corrected figure and note the change date. ## Questions Why would a plant report an OEE above 100%?Usually because the ideal cycle time is set below what the machine can really do, or because production is counted twice. Is a very high OEE always wrong?Not always, but above about 90% on a real packaging line deserves a check of the inputs. ## See this on your lines. [Book a loss review → ](https://recurline.com/demo) ## Keep reading [ Why losses happen · For operations ## The six big losses in manufacturing, end to end Where a plant's productive time really goes: breakdowns, changeovers, minor stops, slow running, scrap and start-up rejects, followed through one shift. 14 Nov 2026 · 3 min read ](https://recurline.com/blog/the-six-big-losses-end-to-end)[ Money and finance · For finance ## What a board pack should say about downtime savings A template for finance and operations: how to report downtime savings to a board with labelled tiers, honest ranges and only confirmed money as ROI. 21 Oct 2026 · 3 min read ](https://recurline.com/blog/what-a-board-pack-should-say-about-downtime-savings)