Quality & Six Sigma

Cost of Poor Quality Calculator

Quantify the true financial impact of defects by combining internal failure, external failure, appraisal and prevention costs — so leadership can see quality losses in pounds, not percentages.

Formula
COPQ = Internal + External + Appraisal + Prevention

Enter your values

Used to express COPQ as a percentage of revenue Enter a valid annual revenue.
Scrap, rework, downtime, re-inspection — caught before reaching the customer
Warranty, returns, complaints, recalls, lost customers — escaped to the customer
Inspection, testing, audits, calibration — the cost of checking
Training, planning, supplier development, process design — the cost of preventing defects
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Ready to calculate

Enter your values on the left, then press Calculate.

Total COPQ
£ per year
% of revenue
World-class gap
COPQ vs world-class (≤2%)
What this means

How it works

Understanding Cost of Poor Quality

1

Four cost categories

Quality costs split into four buckets. Internal and external failure are pure waste. Appraisal is checking — necessary but not value-added. Prevention is the only category that actually reduces total COPQ when you spend more on it.

2

Typical benchmarks

Untouched processes often run at 15-25% of revenue in COPQ — most of it hidden in scrap, rework and inspection. World-class operations hold COPQ below 2% of revenue. The gap between those two figures is usually pure profit waiting to be unlocked.

3

Shift the spend

The fastest way to cut COPQ is to invest more in prevention and less in failure response. Every £1 spent on prevention typically saves £4-£10 in failure costs — but only if the prevention spend is targeted at the actual root causes of defects.