index.md

---

title: AuthenticatorAssertionResponse.userHandle
slug: Web/API/AuthenticatorAssertionResponse/userHandle
page-type: web-api-instance-property
browser-compat: api.AuthenticatorAssertionResponse.userHandle

---

{{APIRef("Web Authentication API")}}{{securecontext_header}}

The userHandle read-only property of the {{domxref("AuthenticatorAssertionResponse")}} interface is an {{jsxref("ArrayBuffer")}} object which is an opaque identifier for the given user. Such an identifier can be used by the relying party's server to link the user account with its corresponding credentials and other data.

This value is set in the id field of the user options object passed in parameter of {{domxref("CredentialsContainer.create()")}} (used for the creation of the PublicKeyCredential instance).

Note: An AuthenticatorAssertionResponse instance is available on {{domxref("PublicKeyCredential.response")}} after calling {{domxref("CredentialsContainer.get()","navigator.credentials.get()")}}.

Note: This property may only be used in top-level contexts and will not be available in an {{HTMLElement("iframe")}} for example.

Value

An {{jsxref("ArrayBuffer")}} object which is an opaque identifier for the current user. This is not human-readable and does not contain any personally identifying information (e.g. username, email, phone number, etc.)

Examples

const options = {
  challenge: new Uint8Array(26), // will be another value, provided by the relying party server
  timeout: 60000,
};

navigator.credentials
  .get({ publicKey: options })
  .then((assertionPKCred) => {
    const userHandle = assertionPKCred.response.userHandle;

    // Send response and client extensions to the server so that it can
    // go on with the authentication
  })
  .catch((err) => console.error(err));

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• {{domxref("CredentialsContainer.create()")}} that sets the value of this property