diff --git a/EXAMPLES.md b/EXAMPLES.md
index 1fc8ca1ee..52ea9eae9 100644
--- a/EXAMPLES.md
+++ b/EXAMPLES.md
@@ -2800,8 +2800,19 @@ To sign up a user with passkey
 ```kotlin
 // Using Coroutines 
 try {
+    val userData = UserData(
+        email = "user@example.com",
+        phoneNumber = "+11234567890",
+        name = "John Doe",
+        givenName = "John",
+        familyName = "Doe",
+        nickName = "johnny",
+        picture = "https://example.com/photo.png",
+        userMetadata = mapOf("signup_source" to "android_app")
+    )
+
     val challenge = authenticationApiClient.signupWithPasskey(
-        "{user-data}",
+        userData,
         "{realm}",
         "{organization-id}"
     ).await()
@@ -2831,7 +2842,19 @@ try {
   <summary>Using Java</summary>
 
 ```java
- authenticationAPIClient.signupWithPasskey("{user-data}", "{realm}","{organization-id}")
+ UserData userData = new UserData(
+    "user@example.com",    // email
+    "+11234567890",        // phoneNumber
+    null,                  // userName
+    "John Doe",            // name
+    "John",                // givenName
+    "Doe",                 // familyName
+    "johnny",              // nickName
+    "https://example.com/photo.png", // picture
+    Map.of("signup_source", "android_app") // userMetadata
+ );
+
+ authenticationAPIClient.signupWithPasskey(userData, "{realm}","{organization-id}")
         .start(new Callback<PasskeyRegistrationChallenge, AuthenticationException>() {
     @Override
     public void onSuccess(PasskeyRegistrationChallenge result) {
diff --git a/auth0/src/main/java/com/auth0/android/authentication/AuthenticationAPIClient.kt b/auth0/src/main/java/com/auth0/android/authentication/AuthenticationAPIClient.kt
index f33aee9ca..1f986e917 100755
--- a/auth0/src/main/java/com/auth0/android/authentication/AuthenticationAPIClient.kt
+++ b/auth0/src/main/java/com/auth0/android/authentication/AuthenticationAPIClient.kt
@@ -313,17 +313,24 @@ public class AuthenticationAPIClient @VisibleForTesting(otherwise = VisibleForTe
      *
      * Example usage:
      *
-     *
      * ```
-     * client.signupWithPasskey("{userData}","{realm}","{organization}")
-     *      .addParameter("scope","scope")
-     *      .start(object: Callback<PasskeyRegistration, AuthenticationException> {
-     *          override fun onSuccess(result: PasskeyRegistration) { }
+     * val userData = UserData(
+     *     email = "user@example.com",
+     *     name = "John Doe",
+     *     givenName = "John",
+     *     familyName = "Doe",
+     *     nickName = "johnny",
+     *     picture = "https://example.com/photo.png",
+     *     userMetadata = mapOf("signup_source" to "android_app")
+     * )
+     * client.signupWithPasskey(userData, "{realm}", "{organization}")
+     *      .start(object: Callback<PasskeyRegistrationChallenge, AuthenticationException> {
+     *          override fun onSuccess(result: PasskeyRegistrationChallenge) { }
      *          override fun onFailure(error: AuthenticationException) { }
      * })
      * ```
      *
-     *  @param userData user information of the client
+     *  @param userData user information for registration.
      *  @param realm the connection to use. If excluded, the application will use the default connection configured in the tenant
      *  @param organization id of the organization to be associated with the user while signing up
      *  @return  a request to configure and start that will yield [PasskeyRegistrationChallenge]
@@ -333,7 +340,6 @@ public class AuthenticationAPIClient @VisibleForTesting(otherwise = VisibleForTe
         realm: String? = null,
         organization: String? = null
     ): Request<PasskeyRegistrationChallenge, AuthenticationException> {
-        val user = gson.toJsonTree(userData)
         val url = auth0.getDomainUrl().toHttpUrl().newBuilder()
             .addPathSegment(PASSKEY_PATH)
             .addPathSegment(REGISTER_PATH)
@@ -351,7 +357,8 @@ public class AuthenticationAPIClient @VisibleForTesting(otherwise = VisibleForTe
             )
         val post = factory.post(url.toString(), passkeyRegistrationChallengeAdapter)
             .addParameters(params) as BaseRequest<PasskeyRegistrationChallenge, AuthenticationException>
-        post.addParameter(USER_PROFILE_KEY, user)
+        post.addParameter(USER_PROFILE_KEY, gson.toJsonTree(userData.toUserProfile()))
+        userData.userMetadata?.let { post.addParameter(USER_METADATA_KEY, it) }
         return post
     }
 
diff --git a/auth0/src/main/java/com/auth0/android/request/UserData.kt b/auth0/src/main/java/com/auth0/android/request/UserData.kt
index 693b64368..f1bc73f6d 100644
--- a/auth0/src/main/java/com/auth0/android/request/UserData.kt
+++ b/auth0/src/main/java/com/auth0/android/request/UserData.kt
@@ -8,10 +8,22 @@ import com.google.gson.annotations.SerializedName
  *  @param phoneNumber the phone number of the user. phone number can be optional, required, or forbidden depending on the attribute configuration for the database
  *  @param userName the username of the user. username can be optional, required, or forbidden depending on the attribute configuration for the database
  *  @param name optional display name
+ *  @param givenName the first name of the user
+ *  @param familyName the last name of the user
+ *  @param nickName the preferred nickname of the user
+ *  @param picture URL pointing to the user's profile picture
+ *  @param userMetadata additional user metadata as key-value pairs
  */
 public data class UserData(
     @field:SerializedName("email") val email: String? = null,
     @field:SerializedName("phone_number") val phoneNumber: String? = null,
     @field:SerializedName("username") val userName: String? = null,
     @field:SerializedName("name") val name: String? = null,
-)
\ No newline at end of file
+    @field:SerializedName("given_name") val givenName: String? = null,
+    @field:SerializedName("family_name") val familyName: String? = null,
+    @field:SerializedName("nickname") val nickName: String? = null,
+    @field:SerializedName("picture") val picture: String? = null,
+    @field:SerializedName("user_metadata") val userMetadata: Map<String, String>? = null,
+) {
+    internal fun toUserProfile(): UserData = copy(userMetadata = null)
+}
\ No newline at end of file
diff --git a/auth0/src/test/java/com/auth0/android/authentication/AuthenticationAPIClientTest.kt b/auth0/src/test/java/com/auth0/android/authentication/AuthenticationAPIClientTest.kt
index 1eb962e33..acc23a85a 100755
--- a/auth0/src/test/java/com/auth0/android/authentication/AuthenticationAPIClientTest.kt
+++ b/auth0/src/test/java/com/auth0/android/authentication/AuthenticationAPIClientTest.kt
@@ -13,6 +13,7 @@ import com.auth0.android.provider.JwtTestUtils
 import com.auth0.android.request.HttpMethod
 import com.auth0.android.request.NetworkingClient
 import com.auth0.android.request.PublicKeyCredentials
+import com.auth0.android.request.UserData
 import com.auth0.android.request.RequestOptions
 import com.auth0.android.request.ServerResponse
 import com.auth0.android.request.internal.RequestFactory
@@ -243,7 +244,7 @@ public class AuthenticationAPIClientTest {
         val auth0 = auth0
         val client = AuthenticationAPIClient(auth0)
         val registrationResponse = client.signupWithPasskey(
-            mock(),
+            UserData(email = "test@example.com"),
             MY_CONNECTION,
             "testOrganization"
         )
@@ -264,6 +265,49 @@ public class AuthenticationAPIClientTest {
         assertThat(registrationResponse.authSession, Matchers.comparesEqualTo(SESSION_ID))
     }
 
+    @Test
+    public fun shouldSignupWithPasskeyWithAllUserDataFields() {
+        mockAPI.willReturnSuccessfulPasskeyRegistration()
+        val auth0 = auth0
+        val client = AuthenticationAPIClient(auth0)
+        val userData = UserData(
+            email = "test@example.com",
+            phoneNumber = "+1234567890",
+            userName = "testuser",
+            name = "Test User",
+            givenName = "Test",
+            familyName = "User",
+            nickName = "testy",
+            picture = "https://example.com/photo.png",
+            userMetadata = mapOf("key1" to "value1")
+        )
+        val registrationResponse = client.signupWithPasskey(
+            userData,
+            MY_CONNECTION,
+            "testOrganization"
+        ).execute()
+        val request = mockAPI.takeRequest()
+        val body = bodyFromRequest<Any>(request)
+        assertThat(request.path, Matchers.equalTo("/passkey/register"))
+        assertThat(body, Matchers.hasKey("user_profile"))
+        @Suppress("UNCHECKED_CAST")
+        val userProfile = body["user_profile"] as Map<String, Any>
+        assertThat(userProfile, Matchers.hasEntry("email", "test@example.com"))
+        assertThat(userProfile, Matchers.hasEntry("phone_number", "+1234567890"))
+        assertThat(userProfile, Matchers.hasEntry("username", "testuser"))
+        assertThat(userProfile, Matchers.hasEntry("name", "Test User"))
+        assertThat(userProfile, Matchers.hasEntry("given_name", "Test"))
+        assertThat(userProfile, Matchers.hasEntry("family_name", "User"))
+        assertThat(userProfile, Matchers.hasEntry("nickname", "testy"))
+        assertThat(userProfile, Matchers.hasEntry("picture", "https://example.com/photo.png"))
+        assertThat(userProfile, Matchers.not(Matchers.hasKey("user_metadata")))
+        assertThat(body, Matchers.hasKey("user_metadata"))
+        @Suppress("UNCHECKED_CAST")
+        val metadata = body["user_metadata"] as Map<String, String>
+        assertThat(metadata, Matchers.hasEntry("key1", "value1"))
+        assertThat(registrationResponse, Matchers.`is`(Matchers.notNullValue()))
+    }
+
     @Test
     public fun shouldGetPasskeyChallenge() {
         mockAPI.willReturnSuccessfulPasskeyChallenge()