Calculate cost of poor quality by summing internal failure and external failure costs. Identify waste reduction opportunities in manufacturing.
Cost of Poor Quality (COPQ) captures the financial impact of producing defective products. It includes internal failure costs — scrap, rework, re-inspection, and downtime caused by defects found before shipment — and external failure costs — warranty claims, product returns, field repairs, customer complaint handling, and recalls triggered by defects that reach the customer.
COPQ is a subset of the broader Cost of Quality (CoQ) framework. While CoQ includes proactive prevention and appraisal spending, COPQ focuses exclusively on the waste generated by quality failures. This makes COPQ a powerful metric for justifying improvement projects: every dollar of COPQ eliminated flows directly to the bottom line.
This calculator lets you itemize internal and external failure costs, calculates total COPQ, and shows it as a percentage of revenue. Use the results to prioritize Six Sigma projects, build business cases for capital equipment, and set quality improvement targets.
By calculating this metric accurately, production managers gain actionable insights that drive continuous improvement efforts and strengthen overall operational performance across the shop floor.
COPQ puts a dollar figure on quality failures that are often hidden in overhead accounts. By isolating and totaling these costs, you create a burning platform for change. COPQ data is the most persuasive argument you can present to leadership for funding quality improvement initiatives. Precise quantification supports benchmarking against industry standards and internal targets, driving accountability and continuous improvement throughout the organization.
COPQ = Internal Failure Costs + External Failure Costs Internal Failure = Scrap + Rework + Re-inspection + Downtime External Failure = Warranty + Returns + Complaints + Recalls COPQ % of Revenue = (COPQ / Annual Revenue) × 100
Result: $250,000 COPQ (5.0% of revenue)
Internal failures total $100,000 (scrap $60K + rework $40K). External failures total $150,000 (warranty $100K + returns $50K). COPQ is $250,000, which is 5.0% of $5M revenue.
Internal failures are cheaper to fix because they are caught before the customer is affected. External failures carry additional costs: shipping, field service, customer relationship damage, and potential regulatory penalties. Shifting detection upstream — from customer complaints to in-process inspection — dramatically reduces COPQ.
Visible COPQ (scrap, rework, warranty) is just the tip of the iceberg. Below the surface lie overtime to recover schedule, excess inventory buffers, lost customer lifetime value, and damaged brand reputation. A thorough COPQ analysis uncovers two to five times more waste than initially expected.
Every COPQ reduction project should have a clear financial charter. Document baseline COPQ, set a target reduction, and measure actual savings post-implementation. Hard dollar savings flow through the income statement and build credibility for future quality investments.
Most manufacturing companies have COPQ between 5% and 25% of revenue. Companies with mature quality systems achieve 1–3%. If you have never measured COPQ, expect to find significant hidden waste.
COPQ includes only failure costs (internal and external). CoQ adds prevention and appraisal costs on top. COPQ highlights waste; CoQ shows total quality-related spending including investments.
Hidden costs include excess inventory held as buffer, over-processing to compensate for variability, lost sales from delivery delays, engineering time spent on corrective actions, and customer churn from dissatisfaction. Keeping detailed records of these calculations will streamline future planning and make it easier to track changes over time.
Use Pareto analysis on COPQ data to identify the top cost drivers. Launch DMAIC projects on the biggest contributors. Invest in prevention — training, mistake-proofing (poka-yoke), and supplier development.
Yes. Include call center time, field service, replacement product costs, and shipping. These are direct external failure costs that would not exist if the product were defect-free.
In theory yes, but in practice no. Even Six Sigma processes have 3.4 defects per million opportunities. The goal is to minimize COPQ, not eliminate it entirely. Diminishing returns set in at very low COPQ levels.