> For the complete documentation index, see [llms.txt](https://docs.1kosmos.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.1kosmos.com/authentication/passwordless-for-web-apps/login-methods/fido-keys/webauthn.md).

# WebAuthn

FIDO2 Web Authentication (WebAuthn) is a standard web API, built into modern web browsers and related web platform infrastructure, used to securely authenticate users across various sites and devices.

***

### Overview

WebAuthn supports two authentication mechanisms, and 1Kosmos supports both:

* **Platform authenticators** - Built into your hardware and often unlocked with biometrics (for example, Touch ID or Face ID).
* **Roaming authenticators (security keys)** - External authentication devices, such as a YubiKey, that connect to your device via USB, NFC, or Bluetooth. Supported on Android and iOS.

### Supported browsers

WebAuthn is currently supported in Google Chrome, Mozilla Firefox, Microsoft Edge, and Apple Safari.

{% hint style="warning" %}
**Incognito browsers:** WebAuthn is not supported in incognito/private browsing modes.
{% endhint %}


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

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

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.1kosmos.com/authentication/passwordless-for-web-apps/login-methods/fido-keys/webauthn.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

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.