Estimator
Enter revenue, defects, and failure costs
Core logic: COPQ = internal failure + external failure + appraisal impact tied to poor quality
Calculator Library / COPQ
Cost of Poor Quality Estimator
Convert defects and failure-related costs into a Cost of Poor Quality model, including internal vs. external failure, sigma-linked defect estimation, and ROI projection for improvement projects.
Breakdown
Failure-cost profile
| Category | Amount | Share | Failure Type |
|---|---|---|---|
| Rework | $57,600 | 11.8% | Internal |
Projection
Improvement project view
Post-improvement COPQ estimate: $368,360
Sigma note: if sigma level input is used, defect rate is estimated from the long-term normal tail probability.
Improvement note: ROI projection assumes the chosen defect reduction target primarily reduces failure-related costs and lost opportunity in the same proportion.
Instructions
How to use this app
- Choose whether to enter the defect rate directly or estimate it from a long-term sigma level.
- Enter production volume, revenue basis, and cost assumptions for rework, scrap, warranty, service recovery, inspection, and lost opportunity.
- Click `Estimate COPQ` to calculate total COPQ, COPQ as a share of revenue, and internal versus external failure costs.
- Enter an improvement-project cost and defect reduction target to see projected annual savings, ROI, and payback.
- Use the sigma-linked mode when you know process sigma level but do not yet have a clean measured defect-rate figure.
COPQ models are only as strong as the cost assumptions behind them. Use this as a directional management tool and refine the cost inputs as your accounting and quality data improve.
Lost opportunity is often the hardest value to estimate. Even a rough, conservative figure is useful because it keeps poor quality from looking cheaper than it really is.
What This Cost of Poor Quality Calculator Does
COPQ turns quality problems into financial language. This estimator helps teams convert defect rates, rework, scrap, inspection burden, warranty exposure, and lost opportunity into a total cost picture that leadership can compare against improvement investment.
It is especially useful when quality engineers need to move a conversation beyond percent defective and into margin, revenue impact, and avoided loss.
Core Cost Logic
| Cost Category | How It Is Used | Typical Examples |
|---|---|---|
| Internal failure | Costs before shipment | Scrap, rework, sorting, downtime, extra inspection. |
| External failure | Costs after escape | Returns, warranty, complaint handling, field service. |
| Appraisal | Costs to detect issues | Inspection labor, test effort, audits, verification checks. |
| Opportunity loss | Commercial impact | Lost sales, margin erosion, delayed launch, damaged trust. |
Worked Example
If a process runs 100,000 units per year at a 2% defect rate, with average scrap/rework cost of $12 per bad unit, $18,000 in additional inspection labor, and $25,000 in annual warranty returns, the direct COPQ already exceeds $67,000 before any lost-sales impact is considered.
Once the defect rate improves, the calculator helps estimate the financial return on a project so the business case is tied to actual process performance, not vague improvement language.
How to Interpret the Output
- High internal failure cost: the process is paying heavily before shipment.
- High external failure cost: the customer is already feeling the process weakness.
- High appraisal cost with weak performance: inspection is not substituting for process control.
- Large ROI upside: the project deserves stronger prioritization and sponsorship.
Cost of Poor Quality Frequently Asked Questions
What is included in COPQ?
COPQ usually includes internal failure, external failure, and often appraisal burden that exists because the process is not trusted to run cleanly.
Is inspection cost part of poor quality?
It can be, especially when inspection is being used to compensate for unstable process design rather than to confirm a stable process.
Why is lost opportunity included?
Because quality problems damage delivery, trust, market share, and margin. The full business impact is often much larger than scrap alone.
How should COPQ be used in project selection?
Use it to rank where quality loss is financially concentrated, then compare likely project savings against implementation cost and effort.
What is the most common COPQ mistake?
Underestimating the hidden costs such as sorting, schedule disruption, expediting, and customer confidence damage.
Related Templates and Guides
Download the PFMEA Template
Use PFMEA to attack the high-cost failure modes before they keep showing up in the COPQ estimate.
Read the Quality Philosophy Foundations Guide
Use it to connect the cost view back to prevention, system design, and leadership responsibility.