Understanding Downtime Percentage
How we calculate. Downtime % = downtime ÷ planned production time × 100. The form uses the same arithmetic as the worked examples on this page. See our methodology and accuracy policy.
Real-world scenario: A typical Downtime Percentage case uses downtime 48 and planned time 480. Enter the same figures below to reproduce the worked path.
What is Downtime Percentage?
A complement to availability (often roughly 100% − availability when definitions align). Split planned vs unplanned downtime in analysis.
- Same unit for both inputs
- Label planned vs unplanned
- Pairs with availability
The Formula
Worked Example
Common Use Cases
- Maintenance: stoppage share
- OEE loss trees: availability losses
- Shift reviews: downtime Pareto
Pro Tips
- Code downtime reasons
- Exclude breaks if planned time excludes them
- Reconcile with availability
Limitations: Downtime Percentage results are educational manufacturing and lean/TPM planning aids—not process-safety, quality-system, or financial advice. Confirm definitions with your MES/SCADA and quality policies.
FAQ
Is downtime % always 100 − availability?
When downtime + run time = planned time and definitions match, yes. Partial overlaps break that identity.
What if planned time is 0?
Downtime % is undefined—enter positive planned time.
Authoritative References
For OEE and manufacturing KPI definitions, consult: