PM Compliance Calculator

How this is calculated

PM compliance (sometimes called PM schedule compliance) measures the share of scheduled preventive maintenance tasks completed on time. Completion rate counts late finishes too, and the gap between the two tells you whether work is slipping or being skipped.

Reading the number

• Grace windows count. Most teams count a PM as on time if it is done within a grace window, commonly 10% of the PM interval (the "10% rule"), for example within 3 days of due on a 30-day PM. Define the window once and hold it steady, otherwise the trend is meaningless.
• Common targets sit around 90% or higher for compliance, stated as a range rather than a fixed standard. What matters most is the trend and which PMs are slipping, especially on critical assets.
• Late is different from missed. A late PM still protects the asset, just less predictably. A missed PM is deferred risk. Watch the missed count even when compliance looks acceptable.
• Compliance is a discipline metric, not a health metric. You can hit 100% on the wrong PM plan. Pair it with breakdown counts to see if the PMs are working.

To weigh what the PM program is worth in dollars, use the preventive maintenance ROI calculator, and to see whether reliability is actually improving, track it with the MTBF, MTTR and availability calculator. For where breakdown hours end up, see the machine downtime guide.