Encoding is critical to the success or failure of RAIN RFID implementations. With billions of RAIN tag chips shipped annually, manufacturers of RAIN-enabled solutions must ensure proper encoding so that each of their products can be reliably identified, operate as expected across compatible systems and contribute to the connected device ecosystem. 

Chris Brown, RFID Program Director at TSC Auto ID Technology, joins us for the second in our three-part tag encoding blog series to share his perspective as a manufacturer of RAIN tag solutions. 

What is tag encoding, and how does it support day-to-day RAIN RFID operations? 

RAIN tag encoding is the process of converting raw data that is typically represented by letters, numbers or logographic characters into binary strings to be stored in tag memory.  Proper tag encoding should follow a standardized format to create an ecosystem where every tag and device speaks the same language, regardless of manufacturer and country of origin.  

The structure and standards to follow are defined by specified encoding schemes, each of which belongs to one of two numbering systems – GS1 EPC and ISO / IEC. A user must first select one of the numbering systems to follow, then select a specific encoding scheme from that system. 

 Each encoding scheme defines the following key parameters: 

  • The data elements, both required and optional, such as the numbering system in use, intended application, serial number, and the entity responsible for the tag’s data. 
  • The character set used for each data element, which may consist of letters, numbers, symbols, or a combination. Different data elements within the same encoding can use different character sets. 
  • The conversion method (table or algorithm) used to translate the characters into the binary data stored on the tag. 
  • The order in which these data elements are encoded. 

Following these rules ensures that tags from different manufacturers and countries of origin are globally unique, do not cause “tag  clutter” (see below), and support interoperability across the supply chain. 

What are the most common mistakes made when encoding RAIN RFID tags, and what impact can they have? 

There are two common mistakes when encoding RAIN RFID tags. The first happens when users try to create their own serial number scheme, rather than adhering to prescribed encoding schemes. For example, a user may prefix all their encodings with a “Z”, believing this makes them unique without accounting for the fact that values encoded in RAIN tags are binary. Depending on how that “Z” is translated into binary, it could easily create a key string of 1s and 0s identical to tags from other applications appearing in the same read zone.  This can result in “tag clutter”, rendering RAIN systems dysfunctional. Standards-based encodings guarantee that the strings of 1s and 0s in tags are truly unique. 

The second common mistake is generating technically invalid or incorrect encodings due to misunderstanding how the standards work. Take SGTIN-96, for example, which is the most common encoding scheme in use today. The scheme takes a product’s UPC / EAN number and adds a serial number to identify each individual instance of that product. This may appear relatively simple, however, in practice, the process is more complex. It requires users to deconstruct the UPC / EAN number into its various data elements, reorganize them, and reconstruct them into a new number. Without a proper understanding of this process, it’s very easy to make a critical mistake. 

Major global retailers and logistics providers are investing billions in RAIN infrastructure – what does this mean for the future of RAIN encoding? 

The future of RAIN RFID is bright. In 2025, the RAIN Alliance reported the shipping of over 42 billion RAIN tag chips – each of which requires robust encoding using standards-based unique numbering. As adoption continues to grow, proper encoding becomes even more vital to avoid a surge in tag clutter and the subsequent ecosystem damage this would cause through increased chance of misreads.  

One particular set of encoding schemes, the ISO-based RAIN Alliance-Issued Company Identification Number (CIN) set, plays a key role in supporting unique numbering and preventing tag clutter.  It is ideal for closed-loop applications, easy to implement, and powerful.  It allows manufacturers to filter between their own tags and those that belong to others.  

For businesses that want to safeguard and future-proof their supply chains, now is the time to ensure their RAIN systems are backed by standards-based encodings that enable effective, efficient tag identification.  

With RAIN technology now recognized as an accepted Digital Product Passport (DPP) data carrier, what are the implications for encoding? 

The common underlying requirement for all accepted DPP data carriers – RAIN tags, NFC, QR codes, for example – is an associated web link with a particular DPP value. This must be either encoded directly into the data carrier as part of the DPP, or the reading device must attach a domain and generate a clickable URL.  

GS1 and ISO both offer encoding schemes that let a RAIN RFID tag store a full URL. If reader software is set up correctly, scanning the tag shows the user a clickable link. This is simple but has two drawbacks. The first is higher manufacturing costs, due to the additional characters of the URL requiring more memory than typical encodings. The second is backwards-compatibility. Many existing RFID systems, including those based on SGTIN-96 used across many high-profile retail deployments, do not store a URL at all. Any DPP solution needs to support incumbent systems without incurring excessive cost. 

The other option would be to rely on reader operating systems (think cellphones here!) to prepend a default domain to the encoding. Rather than encoding full URLs on each tag, the reader’s operating system would add some agreed-on domain and create a clickable URL.   

Making this both functional and compliant with the DPP’s requirement for readability on an “average consumer device” such as a smartphone requires close industry collaboration. RAIN Alliance allows manufacturers of RAIN-enabled products to engage with smartphone providers to agree on which default domains to use, and get those domains built into phone operating systems. This hard, yet vital work is currently underway, determining which domains would be used and when. 

For more on this topic, read our RAIN Alliance Tag Encoding Guide and Specifications here.