RFID

Radio-frequency identification (RFID) is a wireless technology that uses radio waves to identify and track objects, animals or people through small electronic tags. The U.S. Government Accountability Office (GAO) describes it as an automated data-capture technology: a tag attached to or embedded in an item can be read electronically, so nobody has to type in or hand-scan the information. RFID is widely used in logistics, access control, toll collection and livestock management.

History of RFID

The roots of RFID lie in World War II, when military engineers on both sides built on continuous-wave radio methods and produced radar, which locates distant objects with radio waves. Early identification systems combined radar with broadcasting, an idea first proposed in a 1948 paper by the Swedish-born American inventor Harry Stockman.

In the 1950s, researchers developed “identification, friend or foe” transponder networks that worked over long distances. The 1960s brought radar-powered passive data transmission and remotely activated radio devices. In the 1970s, researchers at Los Alamos National Laboratory in New Mexico unveiled a short-range system built on passive tags.

RFID entered everyday commerce in the 1980s. In North America it was used mainly for transportation and for controlling access to restricted places. In Europe it appeared first in agriculture and industry, and in France, Italy, Norway, Portugal and Spain it helped run toll roads. The 1990s saw wider use, including fuel pumps and vehicle access systems built on a Texas Instruments system called TIRIS. The first international standards came from the European Committee for Standardization, for electronic toll collection, and the International Organization for Standardization (ISO), EPCglobal and the International Electrotechnical Commission now handle most RFID standards.

In 1999, Kevin Ashton gave a presentation at Procter & Gamble that linked RFID in the company’s supply chain to the then-fashionable internet. He later wrote that this was probably the first use of the phrase Internet of Things.

How RFID works

An RFID system has three main parts: an antenna, a transceiver and a transponder. The antenna catches the radio signals sent by tags, and the transceiver, which combines a transmitter and a receiver in one unit, works with the antenna to form the reader. The transponder sits inside the tag, receives the reader’s signal and responds with its stored data.

That exchange needs no physical contact. The reader sends out a signal, a tag within range answers, and the reader passes the identifying data to software that records where the tagged item is or what it is. The GAO notes that a tag can also store information about the object it is attached to, which is what makes RFID more flexible than a simple label.

Types of RFID

Tags come in two main kinds. Passive tags have no battery and draw their power from the reader’s signal, so they are easy to maintain because nothing needs replacing when a power source runs out. Active tags carry their own power source and can transmit over longer ranges. Smart labels combine an RFID tag with a barcode, so the same item can be read by either kind of reader.

Systems are also grouped by radio frequency, and each band has its own typical range. Low-frequency RFID works between 30 and 500 kilohertz, commonly at 125 kilohertz, with a range of roughly 6 feet (1.8 meters). High-frequency systems operate between 3 and 30 megahertz, most often at 13.56 megahertz, over a similar distance. Ultra-high frequency (UHF) systems use 300 to 960 megahertz and can read tags from 25 feet (7.6 meters) or more. Microwave RFID, at 2.45 gigahertz, can work beyond 30 feet (9.1 meters).

Choosing a band means balancing read distance against the way tags will be used and the standards that apply in that field.

Applications of RFID

On animals, RFID tags help owners find lost pets and let farmers track individual livestock. In business, the technology is used for inventory control, equipment tracking, cargo shipping and manufacturing, and anywhere else that goods must be tracked without handling them. It is also common in supply chain management, where it makes products visible as they move through distribution networks. Access cards and electronic road toll collection were among its earliest commercial uses, and healthcare is another field that has adopted it.

The GAO reported in 2005 that federal agencies had begun to adopt RFID because falling costs made large-scale use realistic, and its report covered the technology, existing standards, legal questions and security and privacy.

Advantages and disadvantages of RFID

RFID has clear practical strengths. It identifies items without contact, it reads faster than traditional barcode scanning, and passive tags need no battery. A single reader can capture many tagged items in a pass, which saves labor in warehouses and shipping, a process that depends on good inventory management.

It also has costs and risks. Privacy is the most discussed concern, because a tag can be read by anyone with a compatible reader unless protections are added. The EBSCO overview points to unauthorized access to tag data and to surveillance capabilities as the main worries. The U.S. National Institute of Standards and Technology (NIST) published Guidelines for Securing Radio Frequency Identification (RFID) Systems in April 2007. The document explains RFID applications, standards and components and gives practical advice on designing, deploying and operating systems in ways that reduce security and privacy risks.

The details depend on the system. A tag that carries only a short identification number exposes less than one that holds personal information, and a short-range low-frequency tag is harder to read from a distance than a UHF one. Good practice is therefore to decide in advance what a tag should store and who should be able to read it.

RFID vs. barcodes

Barcodes and RFID both identify items, but they work differently. A barcode is printed on a label and must be scanned individually. An RFID tag is read by radio, so identification is contactless and, as the Research Starters overview from EBSCO notes, read times are faster. In practice the two often coexist, because smart labels let a business keep its barcode systems while adding RFID where it brings the most benefit.

Editorially reviewed by Specialty Digest Editorial TeamLast reviewed November 4, 2026Researched and drafted with AI assistanceReport an issue