Cost of Poor Quality Calculator
Total the failure costs of work that was not right first time.
What this calculator does
Addition of the failure categories entered, with optional restatements per unit and as a share of revenue.
Inputs and what they mean
- Currency
- — Amounts are shown in the currency you pick. No exchange rate is applied..
- Internal failure costs (optional)
- — Optional. Leave at 0 to exclude it from the result. Scrap, rework, re-testing, downgrading — found before delivery..
- External failure costs (optional)
- — Optional. Leave at 0 to exclude it from the result. Warranty, returns, recalls, complaint handling — found after delivery..
- Other failure costs you have identified (optional)
- — Optional. Leave at 0 to exclude it from the result. Only costs you have measured yourself. Nothing is added for unmeasured or hidden costs..
- Revenue for the same period (optional)
- — Optional. Leave at 0 to exclude it from the result. Used only to express the total as a share of revenue..
- Good units produced in the period (optional)
- — Optional. Leave at 0 to exclude it from the result. Used only to show the cost per good unit..
How to use it
- Enter your own figures — the calculator never fills in a rate, price or benchmark for you.
- Press Calculate to see the result.
- Read the formula, variables, assumptions and source below the result before you rely on it.
Formula
COPQ = Internal failure + External failure + Other identified failure costs
Worked example
Internal and external failure costs for one quarter
Failure costs only — prevention and appraisal are excluded.
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Limitations and assumptions
Results depend entirely on the figures you enter and are rounded for display. They are for general information and education, not professional advice.
Reference: American Society for Quality — Cost of quality — prevention, appraisal and failure costs
Last reviewed:
Common questions
Formula, source and verification
The failure half of the cost-of-quality model: costs that would disappear if nothing failed. Prevention and appraisal are excluded.
The question it answers: What are we spending on quality, and how much of it is spent on things going wrong?
The formula
COPQ = Internal failure + External failure + Other identified failure costs
- IF — Internal failure
- (currency). Failures found before delivery.
- EF — External failure
- (currency). Failures found after delivery.
- OF — Other identified failure costs
- (currency). Optional. Only failure costs the organisation has measured itself.
- Rev — Revenue
- (currency). Optional. Used only to express the total as a share of revenue.
- U — Good units
- (count). Optional. Used only to show the cost per good unit.
Units: Currency in; currency, percentage and cost per unit out, in the currency selected.
What kind of calculation this is
Deterministic formula. The same inputs always give the same answer. The maths is fixed and does not depend on judgement.
Method
Addition of the failure categories entered, with optional restatements per unit and as a share of revenue.
Assumptions built into the result
- Mathematical: Only failure costs are entered; prevention and appraisal belong to the wider cost of quality.
Figures this calculator will never guess for you
- No benchmark, target or 'world class' value is supplied or implied; the result describes only the figures entered.
- No hidden-cost multiplier or 'iceberg' factor is applied.
- No share of revenue is suggested as normal or acceptable.
- Amounts are shown in the currency selected; no exchange rate is applied.
Limitations
- Unmeasured failure costs — lost sales, reputation, management time — are not included, and no estimate is invented for them.
- The total covers the period whose costs were entered.
- A measured cost of poor quality, an industry benchmark and an organisation's target are three different things.
Source and version
- Standard or reference
- Cost of poor quality — ASQ (ASQ cost of quality: the cost of poor quality comprises internal and external failure costs, excluding prevention and appraisal.)
- Published source
- American Society for Quality — Quality resources
- Formula version
- Version 1
- Verification
- Reviewed against the cited source on
- How much weight the source carries
- Standards or government
- Applies to
- Currency
- Amounts stay in the currency you choose; no exchange rate is applied.
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