---
type: concept
title: Matrix Recovery Key
tags: [matrix, encryption, data-recovery, security]
related: [matrix, matrix-home-server]
created: 2026-06-30
updated: 2026-06-30
sources: ["output/rz_uni_greifswald_de_dienste_allgemein_instant_messaging_chat_matrix_sicherheits.md"]
---

# Matrix Recovery Key

The **Matrix Recovery Key** (Wiederherstellungsschlüssel) is a critical security credential used in the Matrix communication platform to ensure the persistence and recoverability of encrypted message history.

## Technical Necessity
In the Matrix architecture, message keys are stored in an encrypted state on the [[matrix-home-server]] by default. While active sessions can decrypt these messages, a new session or a recovered session requires a way to unlock these keys. The recovery key serves as the master decryption mechanism for this purpose.

## Risks of Omission
If a user does not create a recovery key:
- **Permanent Data Loss**: In the event of a lost session (e.g., device failure, clearing browser cache, or installing a new client), previously written encrypted messages cannot be decrypted.
- **Irreversibility**: Once the session is lost without a recovery key, the encrypted history is effectively gone, as the [[universitatsrechenzentrum-urz]] does not hold the decryption keys.

## Management and Storage
Because the recovery key is the single point of failure for message recovery, it must be stored outside of the Matrix client itself. The URZ recommends using a secure password manager such as [[keepassxc]].