Near-field communication (NFC) is a short-range wireless connectivity technology that uses magnetic field induction to enable communication between devices when they’re touched together or brought within a few centimeters of each other. This includes authenticating credit cards, enabling physical access, transferring small files and jumpstarting more capable wireless links. Broadly speaking, it builds on and extends the work of existing ecosystems and standards around radio frequency ID tags (RFID).

NFC extends RFID and contactless capabilities with more dynamic features enabled by modern smartphones. All modern phones now support NFC chips and applications, such as Apple Pay and Google Pay, to take advantage of the billions of RFID tags and terminals already deployed. NFC makes it easier to load multiple cards into a single phone for payments, municipal transit, building access, opening car doors and other use cases. NFC supports interactive applications built on basic RFID capabilities such as automatically pairing Bluetooth headphones and Wi-Fi connections. It can also automatically pull up data or an app from a poster or ad.

It was originally intended to be used to transfer files between phones using Android Beam. Modern services, such as Google Nearby Share, employ NFC to configure wireless services across faster networks like Bluetooth or Wi-Fi direct.

NFC is limited to short-range communication, which has important implications for physical access security. A user must be within 3.5 inches (10 cm) of an NFC terminal to process a payment or open a door. Another important aspect is that no power is required for the basic mechanics of listening to and responding to NFC requests. This makes it possible to implement in items that lack a battery, such as credit cards.

NFC also complements wireless technologies such as Bluetooth, Ultrawideband (UWB), Wi-Fi direct and QR codes. Its most significant advantage is that it is the easiest wireless technology for setting up a connection, which makes it useful for IoT devices. However, it is not as good at maintaining a connection over distances or for long periods.