Calculator Library / Maintenance
Turn one period of maintenance data into PM compliance, planned work, schedule compliance, backlog weeks, MTBF, and MTTR, and compare them with your own targets.
Tool
Compare six common maintenance measures with targets you set
Targets are editable starting points for discussion, not universal standards. Appropriate levels depend on your industry, assets, and maturity.
Against targets
| KPI | Result | Target | Status | What it tells you |
|---|
Instructions
This calculator turns a month of maintenance data into six commonly used measures: preventive maintenance (PM) compliance, planned work percentage, schedule compliance, backlog in weeks, MTBF, and MTTR. It compares the first four with targets you set, so a team can see at a glance where the maintenance process is under strain.
Use it for monthly reviews, for baselining before an improvement project, and for explaining maintenance performance to operations and finance.
| KPI | Formula | Meaning |
|---|---|---|
| PM compliance | PM completed on time / PM scheduled | How well preventive work is being done when due. |
| Planned work | Planned and scheduled hours / total maintenance hours | How much labor is proactive rather than reactive. |
| Schedule compliance | Scheduled jobs completed as scheduled / jobs scheduled | Whether the weekly plan holds. |
| Backlog (weeks) | Backlog hours of ready work / weekly craft hours available | How long the crews would need to clear ready work. |
| MTBF | Operating hours / failures | Average operating time between failures. |
| MTTR | Repair downtime hours / failures | Average time to restore after a failure. |
The pre-loaded data show 104 of 120 PMs done on time (86.7%), 1,120 of 1,600 labor hours on planned work (70.0%), and 51 of 60 scheduled jobs completed as scheduled (85.0%). Ready backlog is 900 hours against 400 craft hours per week, or 2.25 weeks. Nine failures occurred over 4,320 operating hours, so MTBF is 480 hours, and 72 hours of repair downtime gives an MTTR of 8 hours and availability of 98.4%.
Against the default targets, PM compliance (90%) and planned work (80%) are below target while schedule compliance (85%) and backlog (2 to 4 weeks) are on target. The reading is that the team keeps the week's plan but too much labor still goes to reactive work. The next step is to look at which breakdown causes take the most hours, rather than to push crews harder.
PM compliance is the percentage of scheduled preventive maintenance work orders that were completed on time within a period. It shows how reliably the preventive program is being executed, and definitions of on time, such as within a window of the due date, should be agreed and kept consistent.
Backlog is usually expressed in weeks of work for the available crew. Many maintenance organizations aim for a range of a few weeks, because too little backlog can leave crews idle and too much means work waits too long. The right range depends on your operation, so treat the default range as a starting point.
Planned work is labor spent on jobs that were identified, scoped, and scheduled in advance, which is generally safer and more efficient than reactive work. A low share suggests breakdowns are crowding out planning, and a rising share usually means the preventive and planning processes are working.
Typically from your computerized maintenance management system (CMMS), work-order records, and operating logs. Export one period at a time and keep the definitions consistent, so trends are meaningful.