RC522 RFID Card Reader Writer Module Kit 13.56MHz

The RC522 reads and writes 13.56MHz Mifare-compatible RFID tags over SPI, which is the same short-range contactless technology behind most access cards and transit passes - the module can both read a tag's ID and, on writable tags, store data on them. SPI communication is fast and well-supported, so a microcontroller polling for a nearby tag adds negligible overhead to a project's main loop.

This kit bundles the reader with a Mifare card and a key fob tag, which matters because sourcing compatible tags separately can be the more annoying part of getting started - both are ready to scan the moment the module is wired up, with no separate tag purchase or compatibility guessing.

Common builds are DIY access control systems, attendance tracking, and inventory or asset tagging projects where a low-cost, short-range identification tag is exactly what the job needs.