Your IP:Unknown

·

Your Status: Unknown

Skip to main content


What is an NFC tag, and how does it work?

Near-field communication (NFC) technology is everywhere. That’s why it can be difficult to appreciate how using an NFC tag has optimized our way of living. NFC tags can be found in your digital wallet, in your phone, on public transport, and in restaurants. They’re small and unassuming, but they make our lives a whole lot easier. Here’s how they work.

Nov 10, 2023

10 min read

Wi-Fi authentication

What is an NFC tag?

An NFC tag is a catch-all term referring to any type of technology that can transfer information over short distances. An NFC tag — usually in the form of a chip — can be embedded in almost anything, from stickers to smartphones.

These NFC chips can communicate with each other to exchange, authenticate, or update each other’s data. It’s a system that requires active user input. This makes it excellent if you need to quickly access, verify, or change data without using bigger devices (e.g., data terminal/PC).

How does an NFC tag work?

NFC tags have two important components: the copper coil and the microchip itself. When an NFC reader is brought within four inches of an NFC tag, it uses electromagnetic induction to “broadcast” to the NFC tag. This is received by the copper coil, which then powers the microchip.

This microchip transmits the data to the NFC reader via inductive coupling. The user can then choose what to do with the information that their reader receives. These transactions take place within seconds, making NFC tags a quick and easy way to handle data.

NFC readers like smartphones can store and read hundreds of different NFC tags, making them one of the best devices to utilize NFC technology.

Types of NFC tags

NFC tags can come in different types, depending on the needs of the system using them. These types will usually differ in:

  • Memory — how much data can be stored on the NFC tag itself
  • Transmission speed — how fast data is changed/communicated between NFC tags and devices
  • Usability — the applications where the NFC tag will be used

Given the simple system NFC uses to operate, it can be a highly flexible piece of technology with use in many different industries and applications. This allows NFC users to pick specific types of NFC technology that work best with their intended purpose.

There are five commonly accepted types of NFC tags:

  • Type 1: 90-454 bytes of space, around 106 kilobits per second speed. Special-use chips like the Innovation Topaz.
  • Type 2: 40-140 bytes of space, around 106 kilobits per second speed. General-use chips like the NTAG 203.
  • Types 3: 200—3,000 bytes of space, around 200-400 kilobits per second speed. Specific-use chips like the Sony FeLiCA.
  • Type 4: 1,500-7,500 bytes of space, around 100-400 kilobits per second speed. Secure-use chips like the Desfire 4k.
  • Types 5: 30-8,000 bytes of space, around 400 kilobits per second speed. Industrial-use chips like the EM4233.

Keep in mind that these are general characteristics of NFC tags, and they may differ depending on the usage, manufacturer, and industry they’re being used in. NFC technology is also continuously expanding its infrastructure, which can mean more types of NFC tags available in the future.

Different regulatory bodies govern the types of NFC tags that a business or system must use in its operations. These include the International Standards Organization (ISO), the European Telecommunications Standards Institute (ETSI), and the NFC Forum.

What is an NFC reader?

An NFC reader is any device capable of powering the NFC tag and receiving/transmitting data to it. The most common type of NFC reader that you’ll encounter today is that used for contactless payments. Many smartphones also have NFC capabilities, allowing them to both read and change the information stored on NFC tags.

Benefits of using NFC tags

How exactly did NFC tags and devices gain this much prominence in the way we conduct business? Here are the benefits of using NFC technology:

Convenience and ease of use

By far the biggest argument in favor of using NFC tags is that they’re convenient. Users don’t need to have a deep understanding of how the technology works, the devices that use it, or even the tags themselves.

In most cases, all a user needs to do is to have an NFC reader and point it at the NFC tag.The system does the rest by itself. The inconveniences of using NFC technology (like sometimes requiring an internet connection) are far outweighed by the benefits.

Flexibility in applications

While most NFC applications revolve around financial transactions, the technology comes in handy in plenty of other areas. Because of their small size, ease of operation, and flexible deployment, NFC tags can be integrated with a variety of systems that need to communicate data quickly and efficiently.

Inventory tracking, identity verification, appointment booking, or hygienic concerns can all be addressed with the use of NFC technology. In most cases, all it takes to set up an NFC system are the components of the NFC tag, some work on the data to be stored on them, and then the distribution of these tags.

Optimized resource saving

The resources required to operate an NFC system are readily available. Almost everyone today has a smartphone or another device with NFC capabilities, and the footprint of NFC tags themselves isn’t big. While they may require an upfront cost to manufacture and distribute, not much else needs to be spent on their operation or upkeep.

Unlike terminals, PCs, or other large devices, NFC tags take up little space and don’t require much in terms of power or emissions to use. Not only does this reinforce their convenience for their users, but it also makes them environmentally friendly.

Practical applications of NFC tags

It can be hard to grasp just how versatile NFC tags are because most applications are already ingrained in our day-to-day lives. Here are just a few examples of how NFC technology has made navigating the world around us a little easier.

  1. 1.Unlock your phone. NFC tags can be used to automatically unlock your phone if the tag itself is attached to something you trust. This already happens automatically with things like payment cards or passports, saving you an extra step to getting things done.
  2. 2.Share business cards. Digital business cards can give you more information and actions than physical ones. This is why NFC tags can be so useful for networking. All you need to do is present your tag to someone’s reader, and they’ll get access to your digital brand online, including your entire portfolio of work.
  3. 3.Make payments. NFC technology also powers many of our tap-to-pay systems, reducing the need to fumble with your wallet or even carry around cash. It’s a faster and more secure way of conducting financial transactions and can be done with almost any purchase.
  4. 4.Access control. Many IDs also have NFC tags embedded in them, which grant secure access to workplaces and other areas that need authorization. When combined with biometrics, this adds an extra layer of security. It also makes the workplace far more efficient in terms of user authentication and information sharing.

NFC tags vs. RFID tags

RFIDs use radio waves to transmit data to RFID readers. They can be active (have their own power source to broadcast) or passive (require an external source of power to activate) and can work at longer distances.

Their wireless communication capabilities are like NFCs in this regard, but RFID systems can only broadcast their data. NFC systems can communicate between NFC tags and NFC readers and can contain more complex data than RFID systems.

A good way to frame the differences is to think of RFID tags as megaphones and NFC tags as string telephones. RFID tags can be heard over long distances, but you can only really hear what they’re saying. In contrast, NFC tags don’t have as much distance, but you can freely communicate with whoever’s holding the other end.

How can you use NFC tags with your phone?

Most modern smartphones have NFC capabilities. This allows you to interact with any NFC tag without having to use a dedicated NFC reader to do it. But even if you have NFC on your phone, some phones might have this feature turned off by default.

Here’s how to turn them on depending on your OS.

NFC tags on Android

Android phones will usually have their NFC options in the “Connections” tab of your “Settings.” To enable NFC capabilities, follow these steps:

  1. 1.Go to “Settings.”
  2. 2.Under “Settings,” tap “Connected devices.”
  3. 3.Under “Connected devices,” tap “Connection preferences."
  4. 4.Under “Connection preferences,” tap NFC.
  5. 5.Slide the button to the right to enable your phone’s NFC module.

This is also the best way for you to figure out if your phone supports NFC capabilities. While most modern Android models can automatically interact with NFC tags, some older Android phones do not have this capability.

NFC tags on iPhone

The iPhone IOS is incredibly intuitive with NFC tags. In most cases, all you need to do is to bring your iPhone close to an NFC tag to access it. However, older models may need manual activation.

  1. 1.Go to “Settings.”
  2. 2.Under “Settings,” tap “Control center.”
  3. 3.Under “Control center,” tap the “More controls” section.
  4. 4.Under “More controls,” tap the “+” sign next to the ”NFC tag reader.”
  5. 5.You should now be able to access the NFC tag reader from your iPhone.

If you own an iPhone 11 or higher, it’s likely that it already implements background tag reading with NFC tags. If the screen is lit up and it’s within range of the tag, your iPhone should be able to read the data on it.

NFC tag security issues

Despite their simplicity and ease of use, NFC tags aren’t fully secure. The same convenience that makes them so easy to use also makes them prone to attack. This means users will have to keep these risks in mind whenever they use an NFC system.

Some things to watch out for include:

  • Clone/phishing attacks. Because NFC tags rely on quick authentication to work, it’s possible to “clone” your NFC reader’s information by accessing a compromised or cloned NFC tag. This often happens during phishing attacks, where a user is fooled into trusting a digital interaction that looks legitimate.
  • Identity theft. Like clone or phishing attacks, a compromised NFC tag can also steal your personal information, which can then be sold to bad actors. These actors can use this information to pose as you online and authorize financial transactions and other similar actions in your name.
  • NFC-Bluetooth attacks. Since both are wireless forms of communication, attackers can exploit NFC tags to gain access to the other wireless capabilities of your device or smartphone to steal information or affect your data. These Bluetooth vulnerabilities are often left unsecured by users, which can be a window of vulnerability into your data. Fortunately, most NFC systems have built-in security features to address this issue. It may still happen, but it’s highly unlikely.
  • Financial fraud. The use of NFC tags and technology with wireless payments have made them more vulnerable to attacks from devices like credit card skimmers. Since these devices gain a considerable window to access your finances through your NFC reader, attackers might exploit it to steal your money or purchase things without your approval.

Fortunately, these risks can be mitigated by being smart about how you interact with NFC tags and keeping your devices updated with the latest security software and operating system patches. While it’s not a 100% guarantee that you’ll be protected from all the risks of using NFC technology, taking these actions can often make the difference between a successful attack and an effective deterrent.

Like what you’re reading?

Get the latest stories and announcements from NordVPN

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

We won’t spam and you will always have the choice to unsubscribe

Also available in: Nederlands.


author ilma 1 png

Ilma Vienažindytė

Ilma Vienažindytė is a content manager passionate about technology and online security. In addition to her focus on tech, she also specializes in bringing cybersecurity insights to new markets.