# How many RFID keys can be written to one Hideez Key device?

At the moment, you can write to Hideez Key only one RFID key. Initially, the key stores a unique RFID.

It can be entered into the Access Control System and used without modifications.

If necessary, its (RFID) can be rewritten to any that you selected using the programmer.

The RFID protocol used (125 kHz HID and Em-Marine standard).


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://key.hideez.com/faq/how-many-rfid-keys-can-be-written-to-one-hideez-key-device.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.