A QA matrix, or quality assurance matrix, is a table of defect modes against process stations in flow order. Each cell marks where a defect is made and where it is first caught, and ratings rank the defects so the team fixes the most important first. It is common in TPM and World Class Manufacturing quality work, and each plant sets its own scales.

How is the score calculated in this QA matrix template?

Score = weight × O × D. The weight comes from severity (1, 2, 4, 7 or 10 for severity 1 to 5), O is occurrence from 1 to 5, and D is detection from 1 (caught at the station that made it) to 5 (not caught before the customer). A score of 100 or more is class AA, 50 to 99 is A, 20 to 49 is B and under 20 is C. These are the template's examples, and the Excel version lets you set your own.

What does stations of escape mean?

The number of stations a defect passes between the station that makes it and the first station that catches it. Zero means it is caught at the source. A defect with no catch at all escapes to the customer.

What is the difference between a QA matrix and a PFMEA?

A PFMEA looks at how each process step could fail, rates severity, occurrence and detection and plans controls, often before production starts. A QA matrix starts from the defects you actually see, maps where each one is made and caught along the line and ranks them. Many plants use what the QA matrix shows to update the PFMEA and the control plan.

Where does the data for a QA matrix come from?

Scrap and rework records, NCRs, inspection and test results and customer complaints for a set period, such as the last three months. Count each defect mode once, by the station that makes it, so the occurrence ratings can be compared.

Free template

Updated October 1, 2026

QA matrix template

A QA matrix (quality assurance matrix) is a table of defect modes against the process stations in flow order that marks where each defect is made and where it is first caught. It shows which stations make defects, which checks catch them, how far a defect travels before it is found and which defects reach the customer, so quality work goes where it matters most. There is no single standard format: plants in TPM and World Class Manufacturing programs each set their own scales. Page 1 of the PDF is the matrix for up to 13 defect modes and 8 stations, with severity, occurrence, stations of escape, detection, weight, score, class, rank and an action column, and made-here and caught-here counts for each station. Page 2 has the rating scales, weights and class limits made for this template, the flags and a worked example. The Excel version takes 30 defect modes and 10 stations, works out the made-at and caught-at stations, the stations of escape, detection, score, class and rank, flags defects that reach the customer or are caught late, counts them by class and by station and draws a Pareto of the scores, with the scales on their own sheet so you can set your own.

Free to use: print it, copy it and edit it for your team. Enter your name and work email once to download.

Page 1 of the QA matrix template: fields for product, line, data period, team and date, a key for the M, C and MC marks, and a matrix of 13 defect rows against 8 numbered station columns with severity, occurrence, stations of escape, detection, weight, score, class, rank and action columns, and made-here and caught-here count rows. — Defect modes against stationsMade-here and caught-here marksStations of escapeSeverity, occurrence, detectionWeight × O × D scoreAA, A, B, C class and rankEscape flagsPareto of scores in ExcelWorked example

When to use it

When to use a QA matrix

To decide which defects to work on first when there are more defect types than time: the score ranks them by severity, frequency and how far they travel.
When customer complaints or escapes keep coming back, to see which checks miss which defects and where a check or error-proofing belongs.
When starting quality maintenance in a TPM or World Class Manufacturing program, as the map of where defects are made and caught on a line.
After a process change or a launch, to check that every defect mode has a check close to the station that makes it.

How to fill it in

1
List the stations and the defect modes
Stations across the top in flow order, from the first operation to packing. Defect modes down the side, one per row, from scrap and rework records, NCRs and customer complaints for a set period.
2
Mark where each defect is made and caught
M at the station that makes it, C at the first station that catches it, MC when both happen at one station. No C means the defect reaches the customer.
3
Rate severity and occurrence
Severity from the worst effect if the defect reaches the customer, occurrence from how often it happened in the period. Use the scales on page 2 or your own, the same way for every row.
4
Read detection from the marks
Count the stations between the M and the C. The further the defect travels, the higher D: caught where it is made is 1, not caught at all is 5.
5
Score, class and rank
Score = weight (from severity) × O × D. Class AA, A, B or C from the limits, then rank by score. The weights and limits are the template's examples: agree your own before you score.
6
Act on the top rows
For each top defect, a check at or right after the station that makes it, error-proofing or a fix to the process. Re-score after the change and watch the made-here row.

A filled-in example

Illustrative, not a benchmark

An example: an assembled plastic blower housing, 8 defect modes over 7 stations from molding to final inspection and pack (illustrative, the same numbers as page 2 of the PDF and the Excel worked example).

Screw under-torqued: severity 5 (weight 10), occurrence 2, made at screw fastening and not caught before the customer, so D is 5. Score 10 × 2 × 5 = 100, class AA, rank 1.
Insert not fully seated: severity 4 (weight 7), occurrence 3, made at the insert press and caught at the function test 3 stations later, D 3. Score 7 × 3 × 3 = 63, class A.
Cracked screw boss: made at screw fastening and caught 2 stations later at final inspection, 7 × 2 × 3 = 42. Sink marks travel 6 stations from molding to final inspection: 2 × 4 × 4 = 32.
Wrong label on the box reaches the customer too, but with severity 3 and occurrence 1 it scores 4 × 1 × 5 = 20. Missing screw is caught where it is made: 7 × 2 × 1 = 14. Short shot scores 24 and flash 10.
By class: 1 AA, 1 A, 4 B and 2 C. The scores add up to 305, and the top three (100 + 63 + 42 = 205) are 67.2% of it.

Screw fastening makes three of the eight defects and catches only one, so the first action was a torque check at that station. With it, the under-torqued screw is caught where it is made: D falls from 5 to 1 and its score from 100 to 20.

Common mistakes

Marking only where defects are found
A matrix with C marks and no M marks is an inspection list. The point is the gap between where a defect is made and where it is caught.
Scoring with different scales
If one person's 3 is another's 4, the ranking means nothing. Agree the scales, weights and class limits first and keep them with the matrix.
Letting the score hide an escape
A defect with no C reaches the customer whatever its score. Flag every one and give it a check, even when it ranks low.
Building it once
The matrix is a picture of one period. Update it when the process changes or new defects appear, and re-score after each fix to show the effect.

Download the template

Free to use: print it, copy it and edit it for your team. Enter your name and work email once to download.

Run this template in LeanSuite

In LeanSuite the QA Matrix pulls internal and customer defect data into one place, gives each defect an AA, A, B or C priority from where it was caught, how severe it is, what it costs and how often it recurs, and turns a top defect into a Kaizen or CAPA project in one click.

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