Measure true stage limits before costs escalate. Rank bottlenecks using capacity, losses, and queue pressure. Make smarter improvement decisions with faster, steadier overall flow.
Enter system demand, then compare each stage using true effective capacity rather than nameplate speed.
1) Productive time factor
Productive factor = 1 − (Changeover minutes ÷ Shift minutes)
2) Yield factor
Yield factor = 1 − (Defect rate ÷ 100)
3) Effective capacity
Effective capacity = Design rate × Uptime factor × Yield factor × Productive factor
4) Utilization
Utilization = Demand rate ÷ Effective capacity
5) Queue delay
Queue delay = Queue units ÷ Effective capacity
6) Bottleneck severity score
Severity score = 100 × [0.50 × Utilization ratio + 0.30 × Capacity pressure + 0.20 × Queue pressure]
The highest severity score marks the most restrictive stage. This approach combines capacity loss, demand stress, and waiting pressure into one practical ranking.
| Stage | Design Rate | Uptime | Defect | Queue | Changeover | Effective Capacity | Utilization at 82 units/hr |
|---|---|---|---|---|---|---|---|
| Cutting | 120 | 95% | 1% | 10 | 20 min | 108.22 units/hr | 75.77% |
| Drilling | 105 | 92% | 2% | 16 | 30 min | 88.69 units/hr | 92.46% |
| Welding | 98 | 89% | 3% | 24 | 40 min | 77.56 units/hr | 105.72% |
| Assembly | 110 | 96% | 1% | 12 | 25 min | 99.11 units/hr | 82.74% |
In this example, Welding is the bottleneck because it has the lowest effective capacity and runs above demand.
It identifies the stage most likely to limit system throughput. It also shows demand coverage, queue delay, line balance, and a ranked severity score for every stage.
Design rate ignores downtime, scrap, and setup losses. Effective capacity reflects real operating conditions, so it gives a more reliable view of the true flow limit.
The severity score is a practical ranking index. It blends utilization pressure, capacity weakness, and queue delay so the most restrictive stage appears first.
Yes. You can use it for service desks, warehouses, laboratories, repair centers, and digital workflows wherever work moves through distinct stages.
Use any consistent unit, such as parts, orders, cases, tickets, or tasks. The calculator keeps the same label in the results and exports.
That stage cannot meet current demand under the entered conditions. It should be treated as a priority for improvement, buffering, or load reduction.
Many teams use 80% to 90%. Lower thresholds create earlier warnings, while higher thresholds focus only on stages already operating under strong pressure.
They include the result summary and the ranked stage table. This makes it easier to share bottleneck findings during reviews, planning sessions, and improvement meetings.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.