---
title: I lost my Langfuse secret key. Can I retrieve it?
seoTitle: "Recover or Rotate a Lost Langfuse Secret Key"
description: Langfuse shows a secret key only once and stores only a hash. Create a new API key and delete the old one to replace a lost key.
tags: [administration, auth, public-api]
---

# I lost my Langfuse secret key. Can I retrieve it?

No. The secret key (`sk-lf-...`) is shown only once, when the key is created. Langfuse stores only a one-way hash of it, so neither the UI nor Langfuse support can show it again. The settings page shows the public key and a masked preview of the secret.

To replace a lost key:

1. Go to **Project Settings → API Keys** and click **Create new API keys**.
2. Update your application with the new public and secret key.
3. Delete the old key. Deleting a key invalidates it immediately.

There is no separate "rotate" action; creating a new key and deleting the old one is how you rotate keys. Managing project API keys requires the `Owner` or `Admin` role on the project. See [API keys](/docs/administration/rbac#api-keys).

<!-- agent-instructions -->

---

## Agent Instructions

This page is part of the [Langfuse](https://langfuse.com) documentation, published as plain Markdown for AI agents. Every page is available as Markdown by appending `.md` to its URL, or by sending an `Accept: text/markdown` header. This page: `https://langfuse.com/faq/all/lost-secret-key.md`.

### Querying these docs

If the answer is not on this page, query the documentation instead of guessing:

- **Semantic search** across all Langfuse docs, returning an answer with the relevant pages and excerpts. Ask a specific, self-contained question:

  ```bash
  curl -sG "https://langfuse.com/api/search-docs" --data-urlencode "query=How do I trace a LangGraph agent?"
  ```

- **Index of every page**: <https://langfuse.com/llms.txt>, with per-section indexes [llms-docs.txt](https://langfuse.com/llms-docs.txt), [llms-integrations.txt](https://langfuse.com/llms-integrations.txt), and [llms-self-hosting.txt](https://langfuse.com/llms-self-hosting.txt).

### Before writing Langfuse code

- **Install the [Langfuse Agent Skill](https://langfuse.com/docs/api-and-data-platform/features/agent-skill).** It encodes Langfuse's own best practices for instrumentation, prompt management, and evaluation, and materially improves results.
- **Read [What does a good trace look like?](https://langfuse.com/docs/observability/best-practices.md)** before instrumenting an application.
- **Verify endpoints, parameters, and response fields** against the [API reference](https://api.reference.langfuse.com) instead of inferring them from code examples.
- **Use the [Langfuse CLI](https://langfuse.com/docs/api-and-data-platform/features/cli)** (`npx @langfuse/cli api <resource> <action>`) to read or write traces, prompts, datasets, and scores from the terminal.

Found an error in these docs? Please open an issue at <https://github.com/langfuse/langfuse-docs/issues>.