HF Legacy 
MIFARE Classic 4K
More memory for existing MIFARE Classic systems. Only partially readable by smartphone.
Security Broken
Memory 4 KB
MIFARE Classic® EV1 1K: Technical Data, Security and Use
The MIFARE Classic EV1 1K from NXP is a contactless HF RFID chip for 13.56 MHz. It operates according to ISO/IEC 14443 Type A and has 1 KB of EEPROM, divided into 16 separately configurable sectors. NXP lists access control, employee ID cards, campus cards, parking systems, public transport and loyalty applications, among others, as fields of application.
Today, the chip is mainly of interest for existing systems and reorders. The CRYPTO1 encryption it uses was already attacked in practice in 2008. NXP still lists MIFARE Classic EV1 as an active product, but no longer recommends the product family for new designs. As an alternative, NXP names MIFARE® DESFire® Light.
| Feature | Value |
|---|---|
| Manufacturer | NXP Semiconductors |
| Product family | MIFARE Classic EV1 |
| Type designation | MF1S50yyX/V1 |
| RFID class | HF |
| Frequency | 13.56 MHz |
| Standard | ISO/IEC 14443 Type A |
| Data rate | 106 kbit/s |
| EEPROM | 1,024 bytes |
| Memory structure | 16 sectors of 4 blocks with 16 bytes each |
| Standard data blocks | 47 blocks or 752 bytes outside the sector trailers and manufacturer block |
| Authentication | Mutual three-pass authentication |
| Encryption | CRYPTO1 |
| Key management | Key A and optionally Key B per sector |
| UID | 7-byte UID or 4-byte NUID, depending on the variant |
| Anti-collision | Yes |
| Read range | Up to 100 mm according to NXP, depending on antenna and reader |
| Write cycles | At least 100,000, typically 200,000 at 22 °C |
| Data retention | At least 10 years at 22 °C |
| Smartphone NFC | Limited and device-dependent |
| Product status at NXP | Active – not recommended for new designs |
| Typical media | RFID card, key fob, wristband and special transponders |
| Security rating | Legacy |
| Recommendation | Mainly for existing installations |
NXP specifies 13.56 MHz, 106 kbit/s, an operating distance of up to 100 mm, 1 KB of EEPROM as well as at least 100,000 write cycles and ten years of data retention under the stated test conditions for the chip.
Typical Applications
MIFARE Classic EV1 1K is used today mainly in existing systems.
These include
- access control,
- employee ID cards,
- campus cards,
- public transport,
- parking systems and electronic toll collection,
- loyalty systems and
- existing ticketing solutions.
The chip is particularly often needed for replacement cards and reorders when the readers and backend are already set up for MIFARE Classic.
Suitable media: RFID cards, key fobs, wristbands and special transponders.
Security
Security level: Legacy
MIFARE Classic uses the proprietary CRYPTO1 encryption. The method was already attacked in practice in 2008 and no longer meets today's requirements for security-critical access control systems.
The chip may still be required for existing installations. For new security-critical systems, a current chip family such as MIFARE DESFire should be considered.
Advantages and Disadvantages of MIFARE Classic EV1 1K
| Advantages | Disadvantages |
|---|---|
| Still available for existing systems | CRYPTO1 is considered insecure |
| 16 separate memory areas | Not recommended for new designs |
| Large installed reader base | Smartphone support not universal |
| Many media formats available | Only 752 bytes of regular data area |
Alternatives to MIFARE Classic 1K
Depending on the application, memory requirements and security needs, other chip types may be better suited.
HF / NFC Recommendation 
MIFARE DESFire EV3
For new access control, ID card and multi-application systems.
Security AES-128
Memory 2 / 4 / 8 / 16 KB
HF / NFC Recommendation 
NTAG 213 / 215 / 216
For NFC applications with smartphones and NDEF content.
Security PWD
Memory 144–888 B
Frequently Asked Questions about MIFARE Classic 1K
How much memory does MIFARE Classic 1K have?
MIFARE Classic EV1 1K has 1,024 bytes of EEPROM, divided into 16 sectors of four blocks with 16 bytes each. One block of each sector is reserved as the sector trailer for keys and access rights. In addition, there is the manufacturer block in sector 0. This leaves 47 regular data blocks with a total of 752 bytes. The actual usable capacity may vary slightly depending on how the application is structured.
How secure is MIFARE Classic 1K?
MIFARE Classic uses CRYPTO1 and two 48-bit keys per sector. For today's security-critical applications, this method is considered outdated. Practical attacks were published as early as 2008 that make it possible to read protected data and reconstruct keys. For security-relevant applications, NXP now refers to the MIFARE® DESFire® and MIFARE Plus® product families. New access control systems should therefore no longer rely on MIFARE Classic as a security mechanism.
Can MIFARE Classic 1K be read with a smartphone?
Partially. On Android, support depends on the NFC hardware of the respective smartphone. Android does have its own interface for MIFARE Classic, but supporting it is optional for device manufacturers. A smartphone with NFC therefore does not automatically support all MIFARE Classic functions. Via Core NFC, Apple generally supports communication with MIFARE tags and native MIFARE commands. However, the documentation does not give a general guarantee of full MIFARE Classic support in every use case. If a smartphone application is planned, it should therefore be tested with the intended devices. For simple NFC applications such as URLs or digital business cards, chips from the NTAG family are usually better suited.
Which readers support MIFARE Classic 1K?
The reader must operate at 13.56 MHz and ISO/IEC 14443 Type A and support MIFARE Classic authentication. ISO/IEC 14443 A alone does not guarantee that an existing system can work with the card. MIFARE Classic authenticates access separately for each sector via Key A or Key B. For replacement orders or reorders, the reader, existing encoding and UID variant should therefore be checked. MIFARE Classic EV1 is available with a 7-byte UID and with a 4-byte NUID.
What is the difference between MIFARE Classic 1K and 4K?
The most important difference is the memory. MIFARE Classic 1K has 1 KB of EEPROM, the 4K variant 4 KB. The memory organization also differs: the 1K version has 16 sectors, while MIFARE Classic 4K has a total of 40 sectors. Both variants belong to the same product family and use CRYPTO1. Switching from 1K to 4K gives you more memory, but not up-to-date cryptography.
What is the difference between MIFARE Classic 1K and MIFARE DESFire?
The key difference lies in the security architecture. MIFARE Classic works with CRYPTO1 and a sector-based memory structure. Current products from the MIFARE DESFire family rely on newer cryptographic methods and are therefore better suited for new applications with higher security requirements. NXP itself no longer recommends MIFARE Classic EV1 for new designs and refers to MIFARE DESFire Light as an alternative. For an existing installation, MIFARE Classic 1K can nevertheless be the right choice if the readers and backend expect exactly this chip.
When does MIFARE Classic 1K still make sense today?
The chip makes sense primarily for existing installations. Typical cases are replacement cards, additional employee ID cards or a change of media format, for example from a card to a key fob, if the existing system continues to work with MIFARE Classic. For new security-critical access control systems, a current chip family should be considered. For applications focusing on smartphone NFC, NFC chips designed for this purpose are a better option. NXP still lists MIFARE Classic EV1 as an active product, but no longer recommends it for new designs.
Is MIFARE Classic 1K still being produced?
Yes. NXP currently lists MIFARE Classic EV1 1K with the product status “Active”. At the same time, the manufacturer labels the product as “not recommended for new designs” and recommends MIFARE DESFire Light for new developments. MIFARE Classic 1K therefore remains available for existing systems and replacement needs, but should not automatically be the first choice for a completely new RFID application.