Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The AuthenticatorAssertionResponse interface of the Web Authentication API is returned by CredentialsContainer.get() when a PublicKeyCredential is passed, and provides proof to a service that it has a key pair and that the authentication request is valid and approved.

This interface inherits from AuthenticatorResponse.

AuthenticatorResponse AuthenticatorAssertionResponse

Note: This interface is restricted to top-level contexts. Use from within an <iframe> element will not have any effect.

Instance properties

Also inherits properties from its parent, AuthenticatorResponse.

AuthenticatorAssertionResponse.authenticatorData Secure context Read only

An ArrayBuffer containing information from the authenticator such as the Relying Party ID Hash (rpIdHash), a signature counter, test of user presence and user verification flags, and any extensions processed by the authenticator.

AuthenticatorAssertionResponse.signature Secure context Read only

An assertion signature over AuthenticatorAssertionResponse.authenticatorData and AuthenticatorResponse.clientDataJSON. The assertion signature is created with the private key of keypair that was created during the navigator.credentials.create() call and verified using the public key of that same keypair.

AuthenticatorAssertionResponse.userHandle Secure context Read only

An ArrayBuffer containing an opaque user identifier.

Instance methods



const options = {
  challenge: new Uint8Array([
    /* bytes sent from the server */

  .get({ publicKey: options })
  .then((credentialInfoAssertion) => {
    const assertionResponse = credentialInfoAssertion.response;
    // Do something specific with the response

    // send assertion response back to the server
    // to proceed with the control of the credential
  .catch((err) => console.error(err));


Web Authentication: An API for accessing Public Key Credentials - Level 3
# iface-authenticatorassertionresponse

Browser compatibility

BCD tables only load in the browser

See also