Results
Calculator Inputs
Plotly Graph
The chart compares runtime against planned and unplanned downtime for the current result or the example scenario.
Example Data Table
| Scenario | Scheduled Time (min) | Planned Downtime (min) | Unplanned Downtime (min) | Runtime (min) | Availability (%) | Lost Output (units) |
|---|---|---|---|---|---|---|
| Shift A | 480.00 | 75.00 | 60.00 | 345.00 | 85.19 | 270.00 |
| Shift B | 720.00 | 115.00 | 93.00 | 512.00 | 84.63 | 329.33 |
| Shift C | 600.00 | 65.00 | 45.00 | 490.00 | 91.59 | 201.67 |
Formula Used
| Planned Downtime | Planned Breaks + Planned Maintenance + Setup / Changeover |
|---|---|
| Unplanned Downtime | Breakdown Time + Waiting Delay + Minor Stops |
| Planned Production Time | Scheduled Time − Planned Downtime |
| Runtime | Planned Production Time − Unplanned Downtime |
| Availability % | (Runtime ÷ Planned Production Time) × 100 |
| Uptime % | (Runtime ÷ Scheduled Time) × 100 |
| Downtime % | (Total Downtime ÷ Scheduled Time) × 100 |
| Lost Output | Total Downtime Hours × Ideal Throughput |
| MTBF | Runtime Hours ÷ Failure Count |
| MTTR | Breakdown Hours ÷ Failure Count |
Availability here matches the availability component often used inside OEE analysis.
How to Use This Calculator
- Enter a label for the shift, day, or production period.
- Choose minutes or hours for every time input.
- Add the full scheduled time for the selected period.
- Enter all planned losses, including breaks, maintenance, and setup.
- Enter unplanned losses, including breakdowns, waiting, and minor stops.
- Add failure count for MTBF and MTTR calculation.
- Enter ideal throughput to estimate lost production output.
- Set a target availability value for gap analysis.
- Press the calculate button and review the results above the form.
- Use the CSV and PDF buttons to save the result summary.
FAQs
1. What does availability measure in manufacturing?
Availability shows how much planned production time remained truly productive. It isolates runtime after planned losses are removed, then compares actual runtime against that available production window.
2. Why separate planned and unplanned downtime?
The split reveals different improvement paths. Planned losses need scheduling and planning discipline. Unplanned losses usually need maintenance, process control, material flow, or operator support improvements.
3. Is this calculator useful for OEE work?
Yes. Availability is one of the main OEE components. You can use this result beside performance and quality measures to build a broader OEE view.
4. What should count as planned downtime?
Typical planned downtime includes breaks, scheduled maintenance, sanitation, inspections, setup, changeover, and approved nonproduction events already built into the schedule.
5. What should count as unplanned downtime?
Typical unplanned downtime includes machine failure, waiting for materials, tooling problems, blocked flow, emergency repairs, and short stops that interrupt runtime unexpectedly.
6. What does MTBF tell me?
MTBF estimates average runtime between failures. A rising MTBF usually suggests improving reliability, stronger maintenance control, or fewer interruption events across the measured period.
7. What does MTTR tell me?
MTTR estimates average repair time per failure. Lower MTTR usually means faster response, better spare parts readiness, clearer troubleshooting steps, or improved technician support.
8. How can I improve a low availability score?
Start by ranking the largest downtime categories. Then reduce recurring failures, shorten changeovers, improve material readiness, and standardize recovery actions for frequent stops.