The MIFARE Classic EV1 is the current version of the contactless card pioneer from NXP Semiconductors: it replaces all previous generations of the MIFARE Classic in access badges, transport cards, ticketing, loyalty and employee cards. Compliant with the first levels of the ISO/IEC 14443A standard but built on the same proprietary protocol, it keeps the 1 or 4 kB memory organized into key-protected sectors and the Crypto1 encryption, while adding the 7-byte UID, the Random ID and the originality check. Its compatibility with smartphones is real but partial, and detailed below.
Information
| Manufacturer | NXP Semiconductors |
| Family | MIFARE Classic (EV1 version) |
| References | MF1S50 (1 kB) and MF1S70 (4 kB) |
| Standard | ISO/IEC 14443A (levels 1 to 3) |
| NFC Forum type | None (proprietary NDEF format through the MAD) |
| Operating frequency | 13.56 MHz |
| Data rate | 106 kbit/s |
| Unique identifier (UID) | 7 bytes, or a 4-byte NUID; optional Random ID |
| Encryption | Crypto1 (proprietary), 48-bit keys A and B per sector |
| Operating distance | A few centimeters (up to 100 mm depending on the antenna) |
| Data retention | 10 years |
| Write endurance | 200,000 cycles (typical value) |
| Memory | 1 or 4 kB depending on the version |
Memory
The memory of the MIFARE Classic EV1 is divided into sectors of 16-byte blocks: 16 sectors of 4 blocks on the 1K version; 32 sectors of 4 blocks then 8 sectors of 16 blocks on the 4K version. Each sector ends with a configuration block (the sector trailer):
| Area | Content | Access |
|---|---|---|
| Block 0 (sector 0) | UID and manufacturer data | Read only, set at the factory |
| Data blocks | 16 bytes each; possible value blocks for counters and balances | Read / write according to the sector's access bits |
| Sector trailer (last block of each sector) | Keys A and B, access bits | Governs the sector's read and write rights |
Once the configuration blocks are deducted, the 1K version offers 752 usable bytes and the 4K version 3,440 bytes. Used as an NFC tag, the proprietary MAD format (MIFARE Application Directory) makes it possible to host an NDEF message representing around 700 URL characters on the 1K, and far more on the 4K; reading this NDEF nevertheless depends on the device's compatibility, detailed below.
Features & security
- Per-sector authentication: each sector is protected by two 48-bit keys (key A and key B) verified through a three-pass mutual authentication; the access bits define, key by key, the allowed operations (read, write, increment, decrement).
- Crypto1 encryption: exchanges are encrypted with the proprietary Crypto1 algorithm. Designed in the 1990s, it no longer meets current standards: its weaknesses have been publicly documented since 2008, and the security of a deployment should no longer rely on it alone.
- 7-byte UID and originality check: the EV1 version brings the 7-byte UID (in response to the worldwide exhaustion of 4-byte identifiers, with a 4-byte NUID still available), the optional Random ID for privacy and the NXP originality check to spot counterfeit silicon.
- Value blocks: a block can be formatted as a signed value with a control copy; the increment, decrement and transfer commands execute with an anti-tearing mechanism, the historical toolkit of ticketing.
- Fast transactions: a complete ticketing transaction executes in less than 100 ms, backup management included, with the card able to remain in the wallet during the operation.
- The MIFARE legacy: the de facto standard for contactless badges and tickets, the Classic EV1 fits identically into the existing ecosystem (readers, encoders, cards) and replaces all previous generations without any change to the systems.
NXP now recommends the MIFARE DESFire Light for any new project, with the Classic EV1 still produced for systems already in place. It comes in two capacities (MF1S50 for 1 kB, MF1S70 for 4 kB).
Compatibility
The MIFARE Classic EV1 relies on NFC-A technology (ISO/IEC 14443A), but its proprietary protocol places it outside the tag types standardized by the NFC Forum: compatibility therefore depends on the device's NFC controller. On Android, models equipped with an NXP controller read and write the chip without restriction with NFC Tools; others may be limited to reading the UID. On iPhone, NFC Tools is partially compatible: you need to enable the "compatibility" option in the app settings (iPhone 7 and later, on iOS 15.6 or later).
With NFC Tools, the MIFARE Classic EV1 chip supports, depending on the device, reading technical information as well as reading and writing NDEF records on cards formatted with the MAD. Managing the keys and access bits requires specialized encoding through the chip's dedicated commands. The list of compatible models is available in the article on compatibility.
MIFARE Classic vs MIFARE Classic EV1
| Chip | Memory | Identifier and security | Typical use |
|---|---|---|---|
| MIFARE Classic | 1 or 4 kB | 4-byte identifier, Crypto1 | First generation, historical fleets |
| MIFARE Classic EV1 | 1 or 4 kB | 7-byte UID, Random ID, originality check | The current version, for all fleets |
Both generations share the memory, the protocol and the Crypto1 cipher. The EV1 brings the 7-byte UID (in response to the exhaustion of 4-byte identifiers), the optional Random ID, the NXP originality check and doubled endurance: it powers every card sold today. For a new secure deployment, NXP recommends the MIFARE DESFire Light; for a consumer tag, the NTAG213 and NTAG216 guarantee compatibility with all smartphones.
Frequently asked questions
How much data can be stored on a MIFARE Classic EV1?
1 kB or 4 kB depending on the version, i.e. 752 and 3,440 usable bytes once the configuration blocks are deducted. In the MAD format, the NDEF message represents around 700 URL characters on the 1K version.
What is the difference between MIFARE Classic and MIFARE Classic EV1?
The memory, the protocol and the Crypto1 cipher are identical. The EV1 brings the 7-byte UID (the 4-byte range being exhausted), the optional Random ID, the NXP originality check and doubled write endurance; it replaces all previous generations without any change to the systems.
Is the MIFARE Classic EV1 compatible with iPhones?
Partially. NFC Tools is partially compatible: you need to enable the "compatibility" option in the app settings (iPhone 7 or later on iOS 15.6 or later).
Can a MIFARE Classic EV1 be protected against rewriting?
Yes: the access bits of each sector can forbid writing, a protection reversible by the key holder, or permanent if the access bits lock their own modification. There is no global OTP bit as on NTAG chips.
Useful links
