My barcode has failed verification, what now?

If your barcode has failed verification, this can be frustrating as it delays products going to market. However it is better to know the issues sooner, than have your retailer reject products and require you to redo your packaging and pay for any recall costs. Below are some of the reasons we have experienced for barcode verification failures and what you can do about them:

1. Quiet Zones Too Small

What is it: Barcode scanner needs to know where the barcode starts and stops. Therefore there needs to be a “Quiet Zone” around the barcode, so that there is no interference to reading the barcode from other packaing markings.

If this is too small, you can either (a) reduce the size of the barcode down to minimum 80% magnification or (b) preferably, increase the white space on the side of the barcode where the quiet zone is too small

2. Too many defects

What is it: The white of the barcode needs to be pure white and if it is “dirty” then the barcode will have defects. This means the barcode cannot be read cleanly and reliably

How to fix it: The “dirty” appearance can be caused by

– Poor printing – in which case clean the printing heads

– Packging label that is too thin, causing the background colour of the packaging to come through the label making it “non-white”

3. Non standard barcode encoding

What is it: Barcodes can be encoded in many different ways. You can read more about these here: Retailers will only accept certain types of barcodes. For example Woolworths does not accept 128 barcode types that are not GS1-128 types. You can read about this here. Check section 2.1.4

How to fix it: Make sure that your barcode is printed to the encoding tumes that your retailer requires.



The following information is attached to each barcode report we generate to help you understand the detail of what is being test and what it all means.

What is the Purpose of this Report?

A barcode verification report is required by many retailers to prove that your barcode will reliably scan in the supply chain and at point of sale. This report provides an assessment of the quality of the barcode as printed on the sample provided, and judges if it passes the necessary criteria for reliable scanning.

What is being tested?

Barcode verification is carried out using an an ISO standard barcode verifier (not a simply barcode scanner).The barcode verification process tests a number of technical characteristics of the barcode structure. This includes such things as the contrast between the lines and spaces, the resolution of the printing and the clear space (quiet zones) around the barcode. Together, these technical characteristics determine whether the barcode passes or fails. There are other non-technical aspects, such as barcode positioning that also need to be assessed

How do I evaluate the results?

The barcode is given an overall pass or fail grade as provided on the front page. This determines if the barcode passes the ISO standard. The subsequent tables describe the performance of the barcode vs. the technical characteristics. This helps you to understand how close the barcode is to the various tolerances for each measured characteristic, so that printing can be improved if required.

How frequently should I get my barcode tested?

This report produces a result for a single barcode printed at a point in time. Ideally a barcode should be re-verified every time there is a print run on packaging, as the printing process affects the barcode. Given this can be expensive and laborious, it would be better to do barcode verification yourselves as part of the packaging quality control process (see below)

What if my barcode fails?

Barcodes can fail verification for a variety of reasons and there is extensive reference material available to help understand how to improve barcode quality. If your barcode fails, or just passes, you should consult with your printer and packaging designing to establish how the packaging design or printing process can be improve to make your barcodes more reliable. Appendix J in this document may also help understand reasons for failure:

Where can I get more information?

The glossary on the next few pages gives an overview of the key terms. More reference material can be found here:

How is SKUvantage certified to perform this report?

This report has been produced by SKUvantage employees who have been certified to produce these reports. SKUvantage employees have been trained by Intermax to execute this process as a third party. Intermax are the main vendors of barcode verification equipment and training in Australia.

Can I do barcode verification ourselves?

Your organisation can obtain the same training such that you can do your own verification reports. This will reduce costs and time of developing your packaging material. Yes, this means we don’t get the revenue for this service, but it is the far better solution for our clients. For more informaiton complete the form at


Every  possible effort has been made to ensure that the information and specifications in this report are correct. However, SKUvantage excludes all liability for any errors or omissions, to the maximum extent permitted by law (whether arising in negligence, breach of contract or breach of any other law) that it may have for any loss or damage arising from the use of, or reliance on, this report, whether that loss or damage is direct, indirect or consequential (including loss of any contract or sale, loss of any business revenue, loss of profits, failure to realise expected profits or savings or any other commercial loss or economic loss of any kind).

Glossary of Terms

This glossary summarises what the variables mean and what was tested

TermWhat it means
DescriptionThis is the title of the product as the consumer would see it
Barcode numberA barcode number is represented by a set of lines and spaces that are readable by barcode scanners. This number is usually printed below the barcode.
Barcode typeThis is the “symbology” of the barcode, which is the “language” through which the barcode is encoded. For retail EAN/UPC symbologies are used.
Number of barcodes on productAt least one barcode is needed on items intended for the point of sale. Exceptions are large, heavy or bulky items where two or more symbols with the same GTIN may be required. There should never be two or more barcodes encoding different GTINs on the same product.
Type of printingThis is the method of printing the barcode on the substrate. This may not be easily determined, but can be lithographic, inkjet, gravure etc.
Packaging substrateThe material on which a bar code symbol is printed
ISO Grade (0.0 – 4.0)ISO Verification is a barcode quality testing method based mostly on reflectivity where grading is expressed numerically (4.0-0.0). The result of the test is the measure against this test.
Tested used hand scanner barcode verifierThis shows whether this barcode was tested using a simple hand scanner.
Meets GS1 location recommendationsThis shows whether the placement of the barcode on the packaging meets GS1 standards. The preferred location is on lower right quadrant of the back, respecting quiet zones around the barcode and the edge rule.  More information on location:
Scans using Omni Directional POS scannerThis shows whether this barcode meets the requirements for scanning on a omni-directional scanner, which is the same type of highly reliable scanner used in supermarket checkouts. This type of scanner can cross all of the lines and spaces in a barcode, no matter what the orientation. They are good for reading poorly printed, wrinkled, or even torn barcodes.
Automated scanning in supply chainThis states whether the barcode has met the requirements for scanning in automated scanning environments and achieved the required ISO Symbol                                                                                                                                                                                                                                                                     Grade on the verification test.
Logistical label scanningThis states whether the barcode is being tested as a GS1-128 barcode
TermWhat it means
X Dimension (Magnification)The width of the narrowest element in a barcode e.g. the width of the narrowest bar or space.
Barcode Height & WidthThis is the measured height and width of the barcode. The barcode must be a certain size in order to pass.
Quiet ZonesA clear space which precedes the Start Character of a bar code and follows the Stop Character.  This can also be referred to as “clear area” or “Light Margin”. The quiet zone has to be clear of all text or other graphics so that the scanner and verifier can “see” where the barcode starts and stops.
Correct human readable numberThis confirms that the number under the barcode is the same as the barcode number decoded by the scanner and verifier..
Validity of GS1 Company PrefixThis is the result of whether this barcode is registered to the company producing the product according to the GS1 Prefix and a a Company Number, both of which are allocated by GS1 Member Organisations. If this is not able to be verified through GS1, then the producer must assert they own the barcode.
Data structureThe prime use of this parameter is to report faults when using GS1 data parameters in GS1-128 or GS1 DataBar Expanded.
Symbol StructureThis is used to ensure that the symbol is structured correctly and may also be used to report faults. For example if the check digit is wrong for 128 barcodes, or the bar width ratio is wrong for ITF14 barcodes
DecodeDecode is a pass/fail parameter of whether a barcode can be ‘read’ by a scanner (the bar and space widths can be converted into the correct series of valid characters)
Symbol ContrastThis is the difference between the highest and the lowest levels of reflectance (ie the difference between the darkest bar and lightest space) The higher the value, the better the grade. To improve this, make the bars darker and denser and the spaces lighter or less shiny and not mottled.
Minimum ReflectanceThe least amount of reflectance recorded by the scanner. This is usually achieved from the darkest bar. Ideally it is so dark that it absorbs all light and therefore reflects back 0% light.  To improve this, use a dense ink of a dark colour. Matt is better than gloss for ink density.
Edge ContrastEach transition from a bar to a space, or a space to a bar, treating quiet zones as spaces, is an “edge”. The contrast is determined as the difference between the peak values of space reflectance and bar reflectance in that space and bar. If edge contrast is too low, for example because the black bars are printed on non-white substrate, then the scanner will find it harder to determine the edge of the bars.
ModulationModulation has to do with how a scanner ‘sees’ bars or spaces. Narrow spaces are typically shown as less intense (readable) than wide spaces. The modulation grade can be improved by making narrow spaces slightly wider than the narrow bars.
DefectsDefects are gaps in the bars or spots found in the spaces, or anything in the quiet zone.  Some substrates are more likely to produce defects. Worn or dirty printing plates in wet ink printing can also increase defects.
DecodabiltyDecodability is a pass/fail parameter of a barcode. A barcode will pass on Decode when the bar and space widths can be converted into the correct series of valid characters. If the barcode cannot be decoded, no graphic representation of the barcode is shown.
Bar GainThe increase/decrease in bar width due to effects of the reproduction and printing processes
ISO Pass GradesISO Verification is a barcode quality testing method based mostly on reflectivity where grading is expressed numerically (4.0-0.0)