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Your most asked barcode and standards questions answered

Date: October 14, 2020

Category: Industry news


The world of barcodes and global supply chain standards can be confusing. That is why we asked our resident barcoding expert, Ben Clarke, to provide the answers to some of your most asked barcode and standards questions. 


The Pantry Live

On Tuesday 6 October, the GS1 UK team delivered a masterclass on "How mastering data can increase operational efficiencies, save money and improve customer experience" at The Pantry Live – a virtual event powered by Product Guru to bring together the best of the grocery world in one space. 

The session shared insights on:

  • The increased importance of product data in more digital world
  • Why high-quality product data is becoming a retail priority
  • Seven tips for maximising your master product data

We also took part in an ask-us-anything live Q&A later in the day, where a lot of the questions we received were centred around GTINs and barcodes.

Since this is an area that many of you still have questions on, we thought it would be useful to provide a quick summary of your most frequently asked barcoding questions.

What is a GTIN and how is it regulated? 

GTINs, or Global Trade Item Numbers, are numbers licensed from GS1 that enable unique identification of products and services.

You will find them underneath barcodes on nearly every product in a supermarket. Sometimes called UPC or EAN numbers, GTINs are required by most retailers and online marketplaces in order to sell products.

This is because a GTIN uniquely identifies your product anywhere in the world, which enables your trading partners to track your product throughout the supply chain, ensuring the right product, reaches the right customer, at the right time.

The only place to get legitimate GTINs is directly from GS1. Members of GS1 UK have an online “Numberbank”, where they can allocate GTINs to each product line. We’re here to support you with guidance on how the number should be assigned and when and why they might need to change. 

Do you need a barcode to start selling on Amazon? What do I need to do? 

It depends. If you are popping products in the post direct to the buyer, then you won’t need a barcode. If you are using Fulfilled by Amazon (FBA), then barcodes are used to identify and track inventory throughout the fulfilment process. 

Each item you send to an Amazon Fulfilment Centre requires a barcode. You could either use Amazon barcodes (such as FNSKU), or you could use GS1 barcodes on your items. 

The benefit of using GS1 barcodes is that you can use the same number with all retailers you trade with.

What’s the difference between a barcode from GS1 and others I see online? 

If you obtain numbers from anyone but GS1, the numbers will not be traceable back to you and your brand. These numbers may not be unique, and you may experience problems down the line with your trading partners as a result. 

How many types of barcodes are there and what is a standard barcode format? 

There are lots of different types of barcode. If you are only using barcodes within your own business or for a specific application, then you could just pick whichever one took your fancy. 

If you need to have a barcode that works for your customers and across the supply chain, that’s when you need to use GS1 standards. GS1 have a family of barcodes that are each used in specific scanning environments. For example, our EAN and UPC barcodes can be scanned at point of sale all over the world, whilst our ITF-14 and GS1-128 barcodes are typically used on cases and shippers.

You can find out more about the different types of barcode here.

I have got limited space available on my packaging to integrate a barcode, is there a minimum size or specific ratio required? 

GS1 has defined minimum requirements for barcodes to ensure that they work first time, every time across the supply chain. This does include guidance around height. 

The standard size of an EAN-13 barcode, otherwise known as magnification factor 1.00, means that the width of the barcode is 37.29mm and the height is 22.85mm. The minimum magnification factor used should be 0.80. 

That said, if you’re really struggling for space, we do have a barcode called the EAN-8, which can be printed even smaller than this.

You can find more details on barcode sizes and applying barcodes to packaging here

Can we use different colours for barcodes or do they have to be a combination of black lines over a white background? 

Barcodes must be printed so that the darker bars appear against a paler background. There must also be good contrast between the barcode and spaces. So, black and white is a great combination, although you can also use different combinations.

However, it is not possible to read a barcode if it is reversed out, that is, printed with white lines against a coloured background. Scanners detect the contrast between the bars and spaces using red light, so it is important to use colours that will maximise this contrast.

Some retailers have opted for more use of radio-frequency identification (RFID), could you tell us what are the main difference between RFID and barcodes? Would this impact the future use of barcodes? 

While barcodes are read by some sort of laser or image-based scanner, RFID use radio waves which are captured by a reader. This means that, unlike barcodes, no line of sight is required. 

Another benefit over barcodes is you can read multiple RFID tags simultaneously, which can make identification of things very fast. Tags can also hold a lot more data than barcodes. 

All this means that, depending on what you’re using them for, you can improve inventory accuracy, have higher levels of tracking and visibility of things, and reduce manual labour costs. 

The downside is they are far more expensive than barcodes, so you’re not going to find RFID tags on a can of beans anytime soon.