Although NFC is a subgroup of RFID technology, there are many varieties of NFC tags/inlays to choose from for different solution needs. This page is a summary guide showing common NFC inlay and tag type options available for many common RFID solutions and application needs. This article is a part of the series of articles intended as a practical guide to NFC serving to address many common considerations when selecting an NFC tag type for your unique application or solution.
Types of NFC Tags
Sticker Tags — RFID tags with a self-adhesive backing. Tags come in a variety of shapes and sizes and may be purchased in rolls or strips. Often used for inventory.
Badges & ID Cards — A badge or identification card containing an RFID chip. May come blank or can be customized with logo and/or image. Often used for employee access control badges for work, school, and memberships.
Anti-Metal Tags — On metal RFID tags are designed specifically to work on metal and metallic surfaces. These are commonly used for industrial and enterprise applications.
PROX Tags — Defined as a “contactless” smart card, or keyfob, read by an RFID Reader. Widely used for security and access control. PROX name comes from the word "Proximity" as these are normally used in badges for physical access.
Livestock/Pet Tags — Typically durable plastic commonly attached to the ear of livestock that is used to identify, track, and monitor the animals. These tags are usually read by an RFID wand or RFID antenna. Pet tags are most commonly tiny, glass-encased, low frequency (LF) tags embedded under the animal skin of dogs and cats.
Jewelry Tags — Ideal for inventory and tracking of small items; jewelry tags range from paper-like stickers to plastic tags with punch holes, and more.
Wristband Tags — Come in numerous materials, designs, shapes, and colors. Two common types are single-use and reusable. Often used materials are paper, soft-PVC, and silicone. Customization options for these tags are numerous.
Laundry/Fabric Tags — Fabric tags are sewn into sheets, clothes and other fabrics designed to endure laundry cycles. Common types are silicon and PPS + epoxy covered.
Carrier Tracking Tags — Most commonly are in clip-on/clamp type, zip tie, hanging tag, and lanyard forms for temporary or permanent attachment to carriers used in the manufacturing process and procedures.
Inlay — The NFC "inlay" is the working part of an NFC tag. The inlay is the chip with a connected antenna (e.g., aluminum, copper, silver) bonded to a substrate material that keeps the antenna and chip in place. Inlay substrate is usually a plastic type material a fraction of a millimeter thick. The inlay is commonly covered by durable polymer material such as PET (Polyethylenetherephtalate), PVC (Polyvinyl chloride - credit card type material). For high durability and chemical resistant epoxy resin, PPS (Poly Phenylene Sulfide), Polycarbonate, and ABS (Acrylonitrile Butadiene Styrene) plastic materials work well. The inlay cover can also be paper, which is common for printer applications when the tag durability is not an issue. An inlay covered with silicon is common for reusable wristbands. Inlays are the basis for thousands of applications—they can even be poured into concrete and built into walls. Inlays can be provided “dry” (no adhesive) or “wet” (with adhesive). Wet inlays can have 1-sided or two-sided adhesive and most commonly can come in rolls with one or two release liners.
There are many factors to take into consideration when selecting an NFC tag. The specific type of tag needed depends on factors such as the RFID reader type, read-range, data storage type/size, security features, read/write speed, durability, mounting and environment.
The read range of a given NFC tag primarily depends on both the tag and the RFID reader. Factors such as tag antenna size, and material, RFID reader power, and antenna gain, and the orientation of the RFID reader antenna and the tag antenna.
Inlay Size and material — As one might assume, the larger the inlay, the longer the read range. The tag's inlay refers to the inductively coupled coil within the tag's casing. Typically, a larger tag means that there is a larger inlay (although this is not always the case). Inlay antenna material also affects performance, generally, the copper antenna provides better performance than aluminum. For specific information regarding a tag's inlay size, refer to the manufacturer's documentation and specifications.
RFID Reader/Writer — Today there is a myriad of devices with NFC reading capabilities with a wide range of performance and capability. For example, a smart phone's built-in NFC reader will often need to be held at a closer range than it would if it were a higher-powered reader (such as the idChamp® brand RS3, RS4, NF2, DX1). NFC readers built-in to iPhone X/8/7 do not (as of this article) support writing NFC tags; they are restricted to reading NDEF data from ISO-14443 type tags. Readers like the idChamp® RS4 Reader/Writer can read many NFC tag types (including proprietary types) such as PROX, SEOS, iCLASS, ISO-15694. More adept readers, such as the RS4 mentioned in the previous sentence, can read CSN/UID value of the tag and write NDEF and raw user data formats.
NFC tags come in a variety of different casings/materials, each suited to a specific working environment. Before deciding on an NFC tag type, consider whether or not your implementation will require tags that are temperature-resistant, interference-resistant or water/chemical-resistant.
Outdoor Environments — NFC solutions implemented in outdoor environments often require more durable casing material, such as ABS plastic, PPS + Epoxy, FR4 fiberglass + epoxy resign. You may also consider whether or not the tags will be exposed to moisture from rain or humidity.
Indoor Environments — Indoor environments are typically more technology-friendly and won't require special tag casings or features. However, if you are considering using an NFC solution in an industrial type environment, moisture and other factors may still need to be taken into consideration (albeit, less so than with HF and UHF tags).
High-Interference Environments — High-interference environments are environments where the material the tag is placed on or around negatively impacts that ability to read the tag. These environments are typically conductive surfaces, such as metal. In such instances, you may require tags with anti-metal capabilities.
Different tag types support different data transfer speeds, data store sizes, and features such as anti-collision protocols. To learn more about RFID/NFC tag performance, see our article on improving RFID read ranges.