NFC tag

How does an NFC tag work?

Every NFC tag has two parts: an integrated circuit (the chip) and a coil antenna, usually etched aluminium or copper on a thin plastic carrier. When a phone comes close, its 13.56 MHz field induces a current in the antenna. That current powers the chip, which then answers with the data stored in its memory. The whole exchange takes a fraction of a second, and no battery is involved.

The data on a marketing tag is almost always stored in NDEF (NFC Data Exchange Format), a standard defined by the NFC Forum. An NDEF record can hold a URL, plain text, contact details or Wi-Fi credentials. Phones recognise a URL record and open it in the browser, which is what makes a tag useful in print: the tag does not need to hold the content, only the address of it. The radio technology behind this is explained in our entry on NFC.

Each chip also carries a unique identifier (UID) written at the factory, typically 7 bytes long, which cannot be changed. Some chips can mirror this UID and a tap counter into the URL they return, so a server can tell individual tags apart without encoding a different address on every piece.

Which NFC tag types and chips exist?

The NFC Forum defines five tag types (Type 1 to Type 5), based on different underlying standards. For marketing and packaging, Type 2 tags dominate, mainly the NXP NTAG21x family. Type 4 tags are used where security matters, and Type 5 tags (ISO/IEC 15693) appear in libraries and industrial settings.

• NTAG213: 144 bytes of user memory, enough for a URL of a bit over 130 characters. The most common chip for links on print.
• NTAG215: 504 bytes. Widely used for game figures and cards with more data.
• NTAG216: 888 bytes, for longer records such as a full contact card.
• NTAG 424 DNA (Type 4): generates a cryptographically signed URL on every tap (Secure Unique NFC), used for product authentication and anti-counterfeiting.

What formats do NFC tags come in?

The same chip can be packaged in very different ways. A dry inlay is the chip and antenna on a plastic film with no adhesive, designed to be laminated between layers of paper or board. A wet inlay adds adhesive, and an NFC sticker or label adds a printable face material. There are also NFC cards in PVC or paper, key fobs, wristbands and on-metal tags with a ferrite layer that shields the antenna from metal surfaces.

Size affects range. A larger antenna couples better with the phone and can be read from a little further away, while a very small tag needs the phone to be placed precisely. Because the position of the NFC antenna differs between phones (near the top on iPhones, often mid-back on Android), a printed tap zone should be large and clearly marked.

How are NFC tags used in marketing and print?

In print, an NFC tag is the bridge between a physical piece and a web page. A tag in a mailing, brochure or business card opens a landing page, video or form when tapped. A tag in a package or bottle label can open product information, a registration page or a reorder link, which is the idea behind connected packaging.

Because the URL can point to a redirect on a server, the content can be changed after printing. A campaign that starts with an invitation can later show the event recording, and a broken link can be fixed without reprinting. Locking the tag after encoding prevents anyone from overwriting it.

The honest limits: each tag adds cost to every piece, metal and foil finishes can block the signal, and very thick or heavily laminated stock needs testing. Tags that are glued on as stickers can also be peeled off, which is one reason premium print embeds them between layers instead.

How do you measure what happens after an NFC tag is tapped?

The tag does not record anything itself. Measurement happens in the platform that serves the URL. If each tag carries a unique URL or mirrors its UID, every tap can be tied to a specific piece, batch or recipient. From there, you can count taps and repeat taps, see which content was opened, how long people stayed, and which actions they took. These figures feed into print attribution, the process of connecting offline pieces to digital outcomes.

How does Interactive Paper use NFC tags?

Interactive Paper builds NFC tags into the paper itself rather than sticking them on, so a card or mailer looks and feels like ordinary premium print (320 g/m² for the standard format). Tap uses a single embedded tag that opens a browser experience with video, 3D or AR. Interactive Paper Touch combines NFC chips with conductive ink printed inside the paper to create several touch buttons, a format described on the Touch for print advertising page.

The tags need no battery, so the energy for each interaction comes from the user’s phone. Every tap runs through the Let’s interact platform, which records the interaction and lets the content be updated at any time. For packaging and product labels, Interactive Paper also runs a separate NFC label brand, NFC XR.

Frequently asked questions