The Differences Between a Proximity Card and an RFID Card

The Differences Between a Proximity Card and an RFID Card

by Mike Boehm on March 20, 2023

If you're in the market for access control cards, you'll likely come across two popular options: proximity cards and RFID cards. While both types can serve similar purposes, like granting access to buildings or computer systems, it's essential to understand the differences between the two before making a decision. Knowing the distinction can help you identify which card type is the best fit for your needs and help you make an informed purchasing decision.


Proximity Cards

The simplest definition of proximity cards is as follows: They are access control cards that use RFID technology to communicate with card readers and grant access to secure areas or buildings.


How do proximity cards work?

Proximity cards operate using passive (no battery) technology. Each proximity card contains a small antenna and a microchip that stores data. When the card is brought within range of a proximity reader, the antenna in the card picks up the frequency from the reader, which provides power to the microchip and allows it to transmit data back to the reader. 

The data transmitted by the RFID card includes a unique identifier, like a card number stored as bits, that can be used to authenticate the cardholder's identity and provide access to secured areas or services.


Frequency Range

Proximity cards typically operate on low-frequency (LF) bands, which are in the range of 30 kHz to 300 kHz. The most common frequency for LF RFID systems is 125 kHz. However, it's important to note that the frequency bands for proximity technology systems are not standardized and can vary in range.



RFID cards come in different formats, which are basically different protocols used to store and read data on the card. Some common formats for proximity cards include the Wiegand formats; Keri MS, AWID, DoorKing DK Prox, Indala, and HID 1326 Prox Card II and many more. Each format has its own specifications and is often proprietary to a particular manufacturer or system.



Proximity cards can use different bit formats to store identifying information. The most common bit formats for proximity cards are 26-bit and 35-bit, but other options include 34-bit, 37-bit and 50 bit. 

The 26-bit format is the most widely used and supports up to 65,535 unique ID numbers and 255 facility codes, while the 35-bit format supports up to 1,046,575 unique ID numbers and 4,095 facility codes.


Applications for RFID cards

RFID cards can be used for a wide range of applications, such as time and attendance teaching, transportation, and loyalty programs, but the vast majority of prox cards are used for access control:


Access control

Proximity cards are widely used for access control systems, especially in commercial and government buildings, as well as hospitals and universities. With the use of proximity technology, these cards can be programmed to unlock doors or turnstile gates, providing secure access to authorized individuals only. 

Access control systems using proximity cards are more convenient and easier to use compared to traditional access control methods such as keys, passwords, or PIN codes. The cardholders simply need to hold their card within proximity to the card reader for the reader to detect and recognize the card's unique identification number, granting or denying access depending on the access permissions set in the system.


What are RFID Cards?

The simplest definition of RFID cards is as follows: RFID smart cards are plastic cards or fobs that contain an embedded microchip and use advanced encryption and security features to securely store and transmit data. RFID cards can be used for a variety of purposes, including access control, payment systems, and identification verification. They are designed to be more secure than traditional magnetic stripe cards, or proximity cards, which can easily be copied or cloned. RFID smart cards can communicate with card readers and can be used for both contact and contactless transactions.


How do RFID cards work?

RFID cards operate using a microprocessor chip embedded in the card that can store and process data. The microprocessor chip is typically protected by a layer of security, such as a PIN code or biometric authentication, which is required to access the data stored on the card. 

When a RFID card is inserted into a card reader, the microprocessor chip communicates with the reader to authenticate the card and transfer data between the card and the reader. The data transferred can include personal information, account balances, or digital certificates for secure online transactions.



RFID cards typically operate on high-frequency (HF) or ultra-high-frequency (UHF) bands, depending on their intended use case. High-frequency RFID smart cards generally operate at 13.56 MHz, while ultra-high-frequency smart cards operate between 860 and 960 MHz. The specific frequency used can depend on various factors, such as the type of application or system being used, as well as any applicable regulations or standards.



RFID cards use a variety of formats, including ISO/IEC 7816 and ISO/IEC 14443. One of the most popular types of RFID cards is Mifare.  Mifare cards come in many diferent sub formats such as Classic, Ultralight, 4K plus and more.  These formats define the physical characteristics of the card, the communication protocols used to transmit data between the card and the reader, and the data storage and encryption methods used to secure the information stored on the card.



RFID cards can use a variety of bit structures depending on the specific application and system requirements. The most common bit structures used for RFID smart cards include 32-bit, 64-bit, and 128-bit.


Applications for RFID Smart Cards

The advanced security features and higher storage capacity of RFID cards allow for of effective wider range of applications compared to proximity cards:



In the banking industry, smart cards are now the dominant form of credit and debit cards due to their advanced security features and high storage capacity. The computer chip allows for secure transactions between the cardholder and the bank, reducing the risk of fraud or identity theft.

Some examples of U.S. banks that provide smart cards to customers include JPMorgan Chase, Wells Fargo, and Bank of America.



In the healthcare industry, RFID cards offer a secure and convenient way to store and transfer medical records, insurance information, and other personal health data. With their higher storage capacity and advanced security features, smart cards enable healthcare providers to securely access and transfer patient information, reducing the likelihood of data breaches or privacy violations. 

Smart cards also provide patients with a convenient way to carry their medical records and other important health information with them, making it easier to receive care from different healthcare providers.

This application is emerging and is still not very common, but is expected to see further adoption in the coming years.



RFID cards are used in many public transportation systems across the US, especially in larger metropolitan areas with established public transportation. They provide a convenient way for riders to pay for fares, access stations or vehicles, and store travel data. 

Here are a few examples of metropolitan cities that have implemented RFID cards: 

  • Washington Metropolitan Area Transit Authority (WMATA) – WMATA's smart card system, called SmarTrip, allows riders to load money onto their card and pay for fares on buses and trains in the Washington, DC metropolitan area. 
  • Clipper card system in the San Francisco Bay Area – The Clipper card is a smart card that allows riders to pay for fares on several different transportation systems, including buses, trains, and ferries. 
  • New York City Metropolitan Transportation Authority (MTA) – The MTA uses smart cards for its contactless fare payment system, called OMNY (One Metro New York). With OMNY, riders can pay for fares with a smart card or a mobile device, allowing for a more convenient and streamlined payment process.


Identity authentication

RFID cards are particularly popular for identity authentication, where high levels of security are needed. They can be found in a range of identification cards, such as employee badges, access control cards, and government-issued identification cards, including passports and visas.


Physical and logical access control

RFID smart cards can be used for both physical and logical access control. Physical access control refers to controlling access to buildings, rooms, or other physical spaces, while logical access control refers to controlling access to computer networks, databases, or other digital systems.


Loyalty and rewards programs

Smart cards have gained popularity in customer loyalty and rewards programs in recent years. Smart cards offer the ability to store not only reward points but also demographic and purchase data that is invaluable to the distributing brand. This information can be used to create personalized marketing campaigns, target specific customers and improve overall customer experience. 

Here are a few examples of companies that have started using smart cards for their customer loyalty programs: 

  • Starbucks – uses smart cards for its Starbucks Rewards program, offering customers free drinks, food, and discounts
  • Walgreens – uses smart cards for its Balance Rewards program, allowing customers to earn points and discounts on future purchases
  • Sephora – uses smart cards for its Beauty Insider program that rewards customers with points for purchases, which can then be redeemed for products and experiences. The program also offers exclusive access to events, free beauty classes, and other benefits. 

Secure online transactions

The technology of smart cards is revolutionizing secure online transactions. They are widely used for e-commerce purchases, online banking, and digital signatures. Smart cards enable secure and reliable online transactions by authenticating users and providing a secure channel for data transfer.


Mobile devices

One of the most significant applications of RFID cards is their integration into mobile devices such as smartphones, enabling secure mobile payments and other functions.

For example, some credit card companies issue RFID cards to their customers that can be used for contactless payments using mobile devices. These smart cards can be loaded with payment information and used to pay for goods and services at compatible payment terminals without the need for swiping or inserting a card.


Differences between RFID cards & smart cards

To help you make a decision between these two types of cards, we have created a concise table of important dissimilarities:



Proximity Cards

Smart Cards


RFID, Low frequency, Wiegand format (and many others), up to 37-bits

Microprocessor chips, Ultra high frequency, ISO/IEC 7816 and ISO/IEC 14443, up to 128-bits 

Data storage capacity

Up to 1 Mb

Few Kbs to several Mbs

Security features

Encryption, authentication, some cards have cloning prevention

Cryptographic security including encryption, tamper-resistant design, PIN protection, multi-factor authentication, audit trails, secure communication protocols


Generally, cheaper.

Varies but usually between $1-$5 per card. Discounts are common for large orders.

Generally, more expensive.

Varies but usually between $2-$10 per card. Discounts are common for large orders.


Various but most commonly and best application is access control

Access control, banking, healthcare, transportation, identity authentication, loyalty and reward programs, secure online transactions, mobile devices, and more

Contact vs. contactless




Ready to Buy?

If you are still unsure whether proximity cards or RFID cards are the right choice for your needs, you can turn to the experts at for guidance. Authoriz-ID is a leading provider of access control solutions, including RFID and proximity cards. We offer a wide range of products to suit various needs and budgets, and our team of experts can help you determine which type of card is best for your specific situation. 

If you need help selecting the right product or have any questions about RFID cards or proximity cards, you can reach out to our dedicated support team, available 24/7, at (970) 682-0765 or We will be happy to help you make a decision and place your first order.