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

The PublicKeyCredentialCreationOptions dictionary of the Web Authentication API holds options passed to navigators.credentials.create() in order to create a PublicKeyCredential.



An object describing the relying party which requested the credential creation.


An object describing the user account for which the credential is generated.


A BufferSource, emitted by the relying party's server and used as a cryptographic challenge. This value will be signed by the authenticator and the signature will be sent back as part of AuthenticatorAttestationResponse.attestationObject.


An Array of element which specify the desired features of the credential, including its type and the algorithm used for the cryptographic signature operations. This array is sorted by descending order of preference.

PublicKeyCredentialCreationOptions.timeout Optional

A numerical hint, in milliseconds, which indicates the time the caller is willing to wait for the creation operation to complete. This hint may be overridden by the browser.

PublicKeyCredentialCreationOptions.excludeCredentials Optional

An Array of descriptors for existing credentials. This is provided by the relying party to avoid creating new public key credentials for an existing user who already have some.

PublicKeyCredentialCreationOptions.authenticatorSelection Optional

An object whose properties are criteria used to filter out the potential authenticators for the creation operation.

PublicKeyCredentialCreationOptions.attestation Optional

A String which indicates how the attestation (for the authenticator's origin) should be transported.

PublicKeyCredentialCreationOptions.extensions Optional

An object with several client extensions' inputs. Those extensions are used to request additional processing (e.g. dealing with legacy FIDO APIs credentials, prompting a specific text on the authenticator, etc.).




// some examples of COSE algorithms
const cose_alg_ECDSA_w_SHA256 = -7;
const cose_alg_ECDSA_w_SHA512 = -36;

var createCredentialOptions = {
    // Format of new credentials is publicKey
    publicKey: {
        // Relying Party
        rp: {
            name: "Example CORP",
            id: "",
            icon: ""
        // Cryptographic challenge from the server
        challenge: new Uint8Array(26),
        // User
        user: {
            id: new Uint8Array(16),
            name: "",
            displayName: "John P. Smith",
        // Requested format of new keypair
        pubKeyCredParams: [{
            type: "public-key",
            alg: cose_alg_ECDSA_w_SHA256,
        // Timeout after 1 minute
        timeout: 60000,
        // Do not send the authenticator's origin attestation
        attestation: "none",
        extensions: {
          uvm: true,
          exts: true
        // Filter out authenticators which are bound to the device
          authenticatorAttachment: "cross-platform",
          requireResidentKey: true,
          userVerification: "preferred"
        // Exclude already existing credentials for the user
        excludeCredentials: [
            type: "public-key",
            // the id for
            id  : new Uint8Array(26) /* this actually is given by the server */
            type: "public-key",
            // the id for
            id : new Uint8Array(26) /* another id */

// Create the new credential with the options above
  .then(function (newCredentialInfo) {
    var attestationResponse = newCredentialInfo.response;
    var clientExtensionsOutputs = newCredentialInfo.getClientExtensionsResults();

    // Send the response to the relying party server
    // it will verify the content and integrity before
    // creating a new credential

  }).catch(function (err) {
    // Deal with any error properly


Web Authentication: An API for accessing Public Key Credentials - Level 3 (Web Authentication)
# dictdef-publickeycredentialcreationoptions

Browser compatibility

BCD tables only load in the browser

See also