Your savings, estimated.Then measured.
Enter your own figures. Every saving starts from a published rate at its cautious end, and each rate names its source.
How the estimate worksHow the estimate works.
Each saving multiplies your own figures by one published rate. The calculator starts every rate at the cautious end of its source; the higher figure beside the total uses the upper end. Downtime is counted once, in machine time, and no euro is counted in two places. The connected system's own yearly cost is set against the savings before the payback and the return over three years are worked out.
- Time between programs
People × working hours × time lost to switching × share recovered × cost of an hour.
Across 137 office users at three large companies, Harvard Business Review measured just under four hours a week, 9% of working time, spent reorienting after switching between applications. MES users told MESA International their data entry time fell by 36% and 75% on average in its two surveys; the estimate starts at 36%.
- Software you replace
The yearly licences of the separate programs a connected system replaces.
No published rate is applied: it is what you pay today. Pricing each program you use against one connected system is the usual way to estimate this saving; the connected system's own yearly cost is set against the total below.
- Typing errors
Values typed × working days × error rate × errors avoided = errors avoided a year; × minutes to correct each × cost of an hour.
A review of 93 studies found 0,29% of values wrong when typed once, 0,14% when typed twice and checked, and 6,57% when read from records and copied by hand. Checking each value halves the errors; capturing it at the source removes the copy altogether. The estimate starts at 0,29% and halves it.
- Machine time
Machines × planned hours × current OEE × gain = productive hours gained; × the value of one productive hour, whether as output sold or as overtime and shifts not needed.
Measured across 450 plants, the median OEE was 60%, which is the starting figure here; use your own. One OEE software vendor reports a gain of at least 15% on average among its new clients; the estimate starts at a third of that, 5%.
- Maintenance
Maintenance spend × the share that is reactive × the saving of planned over reactive work.
The US Department of Energy's maintenance guide finds more than 55% of maintenance in the average facility still reactive, and puts the saving of a preventive programme over reactive maintenance at 12% to 18% on average. The estimate starts at 12%.
- Scrap and rework
The cost of scrap and rework × the reduction in defects.
MES users told MESA International their defects fell by 15% and 22% on average in its two surveys. The estimate starts at 15%.
- Work in progress
The value of work in progress × the reduction × the yearly cost of carrying it.
MES users told MESA International their work in progress fell by 17% and 32% on average in its two surveys. Supply chain references commonly put the cost of carrying stock at 15% to 30% of its value a year; the estimate uses 20%.
An estimate is not a measurement. The rates come from other organisations, and your processes decide what you gain. The maturity assessment replaces each assumption with your own data.
Sources
- Rohan Narayana Murty, Sandeep Dadlani and Rajath B. Das, “How Much Time and Energy Do We Waste Toggling Between Applications?”, Harvard Business Review, August 2022. hbr.org
- MESA International, “The Benefits of MES: A Report from the Field”, White Paper 1, revised May 1997. Averages reported by MES users in surveys of 1993 and 1996. mesa.org
- US Department of Energy, Federal Energy Management Program, “Operations & Maintenance Best Practices: A Guide to Achieving Operational Efficiency”, Release 2.0, PNNL-14788, July 2004, chapter 5. pnnl.gov
- Garza and others, “Error Rates of Data Processing Methods in Clinical Research: A Systematic Review and Meta-Analysis”, International Journal of Medical Informatics, 2025. pmc.ncbi.nlm.nih.gov
- TeepTrak, “The 2026 OEE Benchmark Report”, 450 plants in 30 countries, measured by sensors (a vendor's benchmark). teeptrak.com
- Evocon, “OEE Software ROI Calculator” (a vendor's figure for its own clients). evocon.com
- Eurostat, hourly labour costs in 2025, released 31 March 2026. ec.europa.eu
- Inventory carrying cost as commonly given in supply chain references (APICS and others): 15% to 30% of inventory value a year.