Maintenance management without measurement is guesswork. These eight KPIs give a complete picture of how your maintenance operation is performing — from asset reliability to team productivity to cost efficiency. Each one is actionable: when the number moves in the wrong direction, you know exactly what to investigate.
1. MTBF — Mean Time Between Failures
Formula: Total operational hours ÷ number of failures
What it measures: How long assets run, on average, before breaking down.
MTBF is the most direct measure of asset reliability. A pump with an MTBF of 600 hours breaks down twice as often as one with an MTBF of 1,200 hours.
Track MTBF per asset. Assets with declining MTBF are telling you that maintenance is not working — either the interval is too long, the PM procedure is missing something, or the asset is approaching end of life.
Benchmark: Increasing MTBF month over month means your PM program is working.
2. MTTR — Mean Time to Repair
Formula: Total repair hours ÷ number of repairs
What it measures: How long it takes to restore an asset to service after a failure.
MTTR combines three things: how long it takes to diagnose the problem, how long the repair takes, and how long it takes to source parts. A high MTTR often points to a parts problem rather than a technician problem — the repair is quick but the part takes two days to arrive.
Benchmark: MTTR should decrease as technicians gain familiarity with assets and parts stock improves.
3. PM Compliance Rate
Formula: PMs completed on time ÷ PMs scheduled × 100
What it measures: What percentage of your scheduled maintenance actually gets done on time.
PM compliance is a leading indicator — it predicts future failures before they happen. A team with 90% PM compliance will have fewer breakdowns six months from now than a team with 60% compliance.
Benchmark: 80% is a reasonable target for most teams. 90%+ is excellent. Below 60% means the schedule is either unrealistic or the team is too reactive to execute it.
4. Planned vs Reactive Maintenance Ratio
Formula: Hours on planned work ÷ total maintenance hours × 100
What it measures: What proportion of maintenance activity is planned (PM, inspections) versus reactive (emergency repairs, breakdowns).
This ratio reflects the overall maturity of your maintenance operation. A ratio of 80:20 (planned:reactive) is often cited as the target. Most teams starting from scratch are closer to 30:70.
Note: Improving this ratio takes time. It typically takes 6–12 months of consistent PM execution to shift from predominantly reactive to predominantly planned.
5. Overall Equipment Effectiveness (OEE)
Formula: Availability × Performance × Quality
What it measures: How effectively you're using production equipment compared to its maximum potential.
OEE = 85% is considered world-class for discrete manufacturing. Most plants run between 40–60% OEE. The three components identify where losses are occurring:
- Availability losses — unplanned downtime, planned downtime
- Performance losses — slow cycles, minor stops
- Quality losses — defects, rework, startup waste
OEE is a production metric that maintenance directly influences through asset availability. Maintenance managers who understand OEE gain credibility with production management.
6. Work Order Backlog
Formula: Open work orders older than a defined threshold (typically 30 days)
What it measures: How many maintenance jobs are waiting to be done.
A growing backlog is a warning sign. It means either the team is undersized for the workload, reactive work is crowding out planned work, or work order creation has outpaced capacity.
Benchmark: A healthy backlog is 3–4 weeks of planned work. A backlog growing faster than it is cleared needs a root cause investigation.
7. Maintenance Cost per Asset
Formula: Total maintenance spend (labour + parts) ÷ number of maintained assets
What it measures: How much you are spending to maintain each asset per period.
Track this per asset class (pumps, conveyors, HVAC) and compare against replacement cost. When maintenance cost per year exceeds 15–20% of replacement cost, the asset is often a candidate for replacement.
Note: This requires accurate parts costs and labour rates logged against work orders. It is the metric that usually motivates teams to move from paper records to a CMMS.
8. Technician Utilization
Formula: Hours on work orders ÷ available working hours × 100
What it measures: What percentage of technician time is spent on documented maintenance work.
Typical utilization for a well-run maintenance team is 55–70%. Below 40% often indicates too many interruptions, unclear work assignment, or excessive travel/waiting time. Above 80% typically means the team is understaffed and burning out.
Note: Utilization data requires work orders to have time logs. Without time tracking, you are estimating rather than measuring.
Building a Monthly Maintenance Report
A practical monthly report uses six of these eight metrics:
| Metric | This month | Last month | Trend | |--------|-----------|------------|-------| | MTBF (fleet average) | 380 hrs | 340 hrs | ↑ | | MTTR (fleet average) | 2.1 hrs | 2.8 hrs | ↑ | | PM compliance | 84% | 71% | ↑ | | Planned/reactive ratio | 68:32 | 61:39 | ↑ | | WO backlog (30+ days) | 8 | 14 | ↑ | | Maintenance cost/asset | €420 | €480 | ↑ |
Present this to management monthly. When a metric declines, you have the data to explain why and what you're doing about it.
Maintoro calculates MTBF, MTTR, PM compliance, and maintenance costs automatically from your work order and PM data. Reports are available immediately — no spreadsheet assembly required. Free plan available.
Related reading
- MTBF and MTTR: the reliability metrics that matter — formulas, benchmarks, PM-interval setting
- Facility maintenance KPIs — sector-specific metric set
- PM compliance metrics guide — measuring and improving PM execution
- Audit checklist template — KPI evidence for compliance reviews
- CMMS for manufacturing — KPIs in regulated production environments