RFID Mifare Keychain 13.56 MHZ

The RFID Mifare Keychain is a high-quality contactless smart tag designed for use in a wide range of identification, access control, and electronics projects. Built into a compact, durable plastic keychain form factor, this tag is ready to be carried on a keyring, attached to a bag, or used as a personal identification token.

Operating at the globally standard 13.56 MHz frequency, the keychain uses the popular Mifare Classic 1K protocol, providing 1 kilobyte of memory that can be read and rewritten using any compatible RFID/NFC reader. The memory is organized into 16 sectors with 4 blocks per sector, making it ideal for storing user IDs, access credentials, or small data payloads.

This keychain is fully compatible with the most widely-used RFID modules in the maker community, including the MFRC522 (RC522) module commonly used with Arduino, and the more advanced PN532 module that also works with Raspberry Pi and supports full NFC functionality. It's also compatible with commercial RFID readers used in access control and attendance systems.

With its slim 35 × 28 × 4 mm dimensions and attractive blue color, the keychain is both practical and discreet. Whether you're building a smart door lock, attendance system, inventory tracker, or learning RFID technology for the first time, this keychain is an excellent and cost-effective choice.

Specifications

• Type: Mifare Classic 1K Keychain Tag
• Operating Frequency: 13.56 MHz
• Memory: 1K (1024 bytes)
• Memory Structure: 16 sectors × 4 blocks (16 bytes per block)
• Protocol: ISO/IEC 14443 Type A
• Read/Write Distance: Typically 2 to 5 cm (depends on reader)
• Color: Blue
• Dimensions: 35 mm × 28 mm × 4 mm
• Material: Durable ABS plastic
• Compatibility: MFRC522 (RC522), PN532, and other 13.56 MHz Mifare-compatible readers
• Power Source: Passive (no battery required — powered by the reader's RF field)
• Data Retention: More than 10 years
• Read/Write Cycles: More than 100,000 times
• Operating Temperature: -20°C to +55°C

Compatibility

This keychain works with virtually all 13.56 MHz Mifare Classic-compatible RFID readers, including:

• MFRC522 (RC522) RFID Reader/Writer Module — most common with Arduino
• PN532 NFC/RFID Module — works with Arduino, Raspberry Pi, and ESP32
• ACR122U USB NFC Reader/Writer
• Commercial RFID access control systems
• Standard RFID attendance and time-tracking devices

Applications

• Access Control Systems – Door locks, gates, and secure entry points
• Attendance Tracking – Schools, offices, and workshops
• Membership Cards – Gyms, clubs, libraries, and loyalty programs
• DIY Smart Locks – Build your own Arduino or ESP32-based door lock
• Inventory Management – Tag and track equipment, tools, and assets
• Maker & Hobbyist Projects – RC522 and PN532 RFID experiments
• Educational Use – Learn RFID technology in labs and classrooms
• Personal Identification – Carry your ID conveniently on a keyring
• Hotel & Office Key Replacement – Add to existing key sets
• Event Access Passes – Conferences, exhibitions, and ticketed events