diff --git a/BlazorWasmDemo/Server/Controllers/UserController.cs b/BlazorWasmDemo/Server/Controllers/UserController.cs
index 5b648d00..cce465ce 100644
--- a/BlazorWasmDemo/Server/Controllers/UserController.cs
+++ b/BlazorWasmDemo/Server/Controllers/UserController.cs
@@ -265,7 +265,7 @@ public async Task<string> MakeAssertionAsync([FromBody] AuthenticatorAssertionRa
             _pendingAssertions.Remove(key);
 
             // 2. Get registered credential from database
-            var creds = _demoStorage.GetCredentialById(clientResponse.Id) ?? throw new Exception("Unknown credentials");
+            var creds = _demoStorage.GetCredentialById(clientResponse.RawId) ?? throw new Exception("Unknown credentials");
 
             // 3. Make the assertion
             var res = await _fido2.MakeAssertionAsync(new MakeAssertionParams
diff --git a/Demo/Controller.cs b/Demo/Controller.cs
index 367a30c1..1b745036 100644
--- a/Demo/Controller.cs
+++ b/Demo/Controller.cs
@@ -194,7 +194,7 @@ public async Task<JsonResult> MakeAssertion([FromBody] AuthenticatorAssertionRaw
             var options = AssertionOptions.FromJson(jsonOptions);
 
             // 2. Get registered credential from database
-            var creds = DemoStorage.GetCredentialById(clientResponse.Id) ?? throw new Exception("Unknown credentials");
+            var creds = DemoStorage.GetCredentialById(clientResponse.RawId) ?? throw new Exception("Unknown credentials");
 
             // 3. Get credential counter from database
             var storedCounter = creds.SignCount;
diff --git a/Demo/TestController.cs b/Demo/TestController.cs
index 22758728..c12a1414 100644
--- a/Demo/TestController.cs
+++ b/Demo/TestController.cs
@@ -181,7 +181,7 @@ public async Task<JsonResult> MakeAssertionTestAsync([FromBody] AuthenticatorAss
         var options = AssertionOptions.FromJson(jsonOptions);
 
         // 2. Get registered credential from database
-        var creds = _demoStorage.GetCredentialById(clientResponse.Id);
+        var creds = _demoStorage.GetCredentialById(clientResponse.RawId);
 
         // 3. Get credential counter from database
         var storedCounter = creds.SignCount;
diff --git a/Src/Fido2.Models/AuthenticatorAssertionRawResponse.cs b/Src/Fido2.Models/AuthenticatorAssertionRawResponse.cs
index 92d814c1..94f9e427 100644
--- a/Src/Fido2.Models/AuthenticatorAssertionRawResponse.cs
+++ b/Src/Fido2.Models/AuthenticatorAssertionRawResponse.cs
@@ -12,9 +12,11 @@ namespace Fido2NetLib;
 /// </summary>
 public class AuthenticatorAssertionRawResponse
 {
-    [JsonConverter(typeof(Base64UrlConverter))]
+    /// <summary>
+    /// A string containing the credential's identifier. Base64UrlEncoding of <seealso cref="RawId"/>.
+    /// </summary>
     [JsonPropertyName("id"), Required]
-    public byte[] Id { get; init; }
+    public string Id { get; init; }
 
     // might be wrong to base64url encode this...
     [JsonConverter(typeof(Base64UrlConverter))]
diff --git a/Src/Fido2.Models/AuthenticatorAttestationRawResponse.cs b/Src/Fido2.Models/AuthenticatorAttestationRawResponse.cs
index 06cddf99..1a124b5c 100644
--- a/Src/Fido2.Models/AuthenticatorAttestationRawResponse.cs
+++ b/Src/Fido2.Models/AuthenticatorAttestationRawResponse.cs
@@ -9,9 +9,11 @@ namespace Fido2NetLib;
 
 public sealed class AuthenticatorAttestationRawResponse
 {
-    [JsonConverter(typeof(Base64UrlConverter))]
+    /// <summary>
+    /// A string containing the credential's identifier. Base64UrlEncoding of <seealso cref="RawId"/>.
+    /// </summary>
     [JsonPropertyName("id"), Required]
-    public byte[] Id { get; init; }
+    public string Id { get; init; }
 
     [JsonConverter(typeof(Base64UrlConverter))]
     [JsonPropertyName("rawId"), Required]
diff --git a/Src/Fido2/AuthenticatorAssertionResponse.cs b/Src/Fido2/AuthenticatorAssertionResponse.cs
index bf94b4a5..f578338c 100644
--- a/Src/Fido2/AuthenticatorAssertionResponse.cs
+++ b/Src/Fido2/AuthenticatorAssertionResponse.cs
@@ -77,7 +77,7 @@ public async Task<VerifyAssertionResult> VerifyAsync(
         if (options.AllowCredentials != null && options.AllowCredentials.Any())
         {
             // might need to transform x.Id and raw.id as described in https://www.w3.org/TR/webauthn/#publickeycredential
-            if (!options.AllowCredentials.Any(x => x.Id.SequenceEqual(Raw.Id)))
+            if (!options.AllowCredentials.Any(x => x.Id.SequenceEqual(Raw.RawId)))
                 throw new Fido2VerificationException(Fido2ErrorCode.InvalidAssertionResponse, Fido2ErrorMessages.CredentialIdNotInAllowedCredentials);
         }
 
@@ -87,7 +87,7 @@ public async Task<VerifyAssertionResult> VerifyAsync(
             if (UserHandle.Length is 0)
                 throw new Fido2VerificationException(Fido2ErrorMessages.UserHandleIsEmpty);
 
-            if (await isUserHandleOwnerOfCredId(new IsUserHandleOwnerOfCredentialIdParams(Raw.Id, UserHandle), cancellationToken) is false)
+            if (await isUserHandleOwnerOfCredId(new IsUserHandleOwnerOfCredentialIdParams(Raw.RawId, UserHandle), cancellationToken) is false)
             {
                 throw new Fido2VerificationException(Fido2ErrorCode.InvalidAssertionResponse, Fido2ErrorMessages.UserHandleNotOwnerOfPublicKey);
             }
@@ -177,7 +177,7 @@ public async Task<VerifyAssertionResult> VerifyAsync(
 
         return new VerifyAssertionResult
         {
-            CredentialId = Raw.Id,
+            CredentialId = Raw.RawId,
             SignCount = authData.SignCount,
             IsBackedUp = authData.IsBackedUp
 
diff --git a/Tests/Fido2.Tests/Attestation/Apple.cs b/Tests/Fido2.Tests/Attestation/Apple.cs
index 06a8d704..22ceaf1f 100644
--- a/Tests/Fido2.Tests/Attestation/Apple.cs
+++ b/Tests/Fido2.Tests/Attestation/Apple.cs
@@ -224,7 +224,7 @@ public async Task TestApplePublicKeyMismatch()
         var attestationResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
diff --git a/Tests/Fido2.Tests/AuthenticatorResponse.cs b/Tests/Fido2.Tests/AuthenticatorResponse.cs
index 8ce33b76..e7aaf7c5 100644
--- a/Tests/Fido2.Tests/AuthenticatorResponse.cs
+++ b/Tests/Fido2.Tests/AuthenticatorResponse.cs
@@ -75,7 +75,7 @@ public async Task TestAuthenticatorOriginsAsync(string origin, string expectedOr
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -181,7 +181,7 @@ public async Task TestAuthenticatorOriginsFail(string origin, string expectedOri
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -253,7 +253,7 @@ public void TestAuthenticatorAttestationRawResponse()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -284,7 +284,7 @@ public void TestAuthenticatorAttestationRawResponse()
             }
         };
         Assert.Equal(PublicKeyCredentialType.PublicKey, rawResponse.Type);
-        Assert.Equal([0xf1, 0xd0], rawResponse.Id);
+        Assert.Equal("8dA", rawResponse.Id);
         Assert.Equal([0xf1, 0xd0], rawResponse.RawId);
         Assert.Equal([0xa0], rawResponse.Response.AttestationObject);
         Assert.Equal(clientDataJson, rawResponse.Response.ClientDataJson);
@@ -311,7 +311,7 @@ public void TestAuthenticatorAttestationResponseNull()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = null
         };
@@ -398,7 +398,7 @@ public async Task TestAuthenticatorAttestationResponseInvalidType()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -457,9 +457,9 @@ public async Task TestAuthenticatorAttestationResponseInvalidType()
     }
 
     [Theory]
-    [InlineData(null)]
-    [InlineData(new byte[0])]
-    public async Task TestAuthenticatorAttestationResponseInvalidRawId(byte[] value)
+    [InlineData(null, null)]
+    [InlineData("", new byte[0])]
+    public async Task TestAuthenticatorAttestationResponseInvalidRawId(string value, byte[] rawValue)
     {
         var challenge = RandomNumberGenerator.GetBytes(128);
         var rp = "https://www.passwordless.dev";
@@ -474,7 +474,7 @@ public async Task TestAuthenticatorAttestationResponseInvalidRawId(byte[] value)
         {
             Type = PublicKeyCredentialType.PublicKey,
             Id = value,
-            RawId = value,
+            RawId = rawValue,
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
                 AttestationObject = new CborMap {
@@ -546,7 +546,7 @@ public async Task TestAuthenticatorAttestationResponseInvalidRawType()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.Invalid,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -626,7 +626,7 @@ public async Task TestAuthenticatorAttestationResponseRpidMismatch()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -707,7 +707,7 @@ public async Task TestAuthenticatorAttestationResponseNotUserPresentAsync()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -790,7 +790,7 @@ public async Task TestAuthenticatorAttestationResponseBackupEligiblePolicyRequir
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -871,7 +871,7 @@ public async Task TestAuthenticatorAttestationResponseBackupEligiblePolicyDisall
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -952,7 +952,7 @@ public async Task TestAuthenticatorAttestationResponseNoAttestedCredentialData()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -1033,7 +1033,7 @@ public async Task TestAuthenticatorAttestationResponseUnknownAttestationType()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -1114,7 +1114,7 @@ public async Task TestAuthenticatorAttestationResponseNotUniqueCredId()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -1194,7 +1194,7 @@ public async Task TestAuthenticatorAttestationResponseUVRequired()
         var rawResponse = new AuthenticatorAttestationRawResponse
         {
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             Response = new AuthenticatorAttestationRawResponse.AttestationResponse
             {
@@ -1275,7 +1275,7 @@ public void TestAuthenticatorAssertionRawResponse()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs
             {
@@ -1301,7 +1301,7 @@ public void TestAuthenticatorAssertionRawResponse()
             }
         };
         Assert.Equal(PublicKeyCredentialType.PublicKey, assertionResponse.Type);
-        Assert.Equal([0xf1, 0xd0], assertionResponse.Id);
+        Assert.Equal("8dA", assertionResponse.Id);
         Assert.Equal([0xf1, 0xd0], assertionResponse.RawId);
         Assert.Equal([0xf1, 0xd0], assertionResponse.Response.AuthenticatorData);
         Assert.Equal([0xf1, 0xd0], assertionResponse.Response.Signature);
@@ -1352,7 +1352,7 @@ public async Task TestAuthenticatorAssertionTypeNotPublicKey()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.Invalid,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs
             {
@@ -1504,7 +1504,7 @@ public async Task TestAuthenticatorAssertionRawIdMissing()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs()
             {
                 AppID = false,
@@ -1579,7 +1579,7 @@ public async Task TestAuthenticatorAssertionUserHandleEmpty()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs()
             {
@@ -1655,7 +1655,7 @@ public async Task TestAuthenticatorAssertionUserHandleNotOwnerOfPublicKey()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs()
             {
@@ -1731,7 +1731,7 @@ public async Task TestAuthenticatorAssertionTypeNotWebAuthnGet()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs
             {
@@ -1809,7 +1809,7 @@ public async Task TestAuthenticatorAssertionAppId()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs()
             {
@@ -1886,7 +1886,7 @@ public async Task TestAuthenticatorAssertionInvalidRpIdHash()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs()
             {
@@ -1964,7 +1964,7 @@ public async Task TestAuthenticatorAssertionUPRequirementNotMet()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs
             {
@@ -2041,7 +2041,7 @@ public async Task TestAuthenticatorAssertionUVPolicyNotMet()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs
             {
@@ -2116,7 +2116,7 @@ public async Task TestAuthenticatorAssertionBEPolicyRequired()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs()
             {
@@ -2192,7 +2192,7 @@ public async Task TestAuthenticatorAssertionBEPolicyDisallow()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs
             {
@@ -2268,7 +2268,7 @@ public async Task TestAuthenticatorAssertionBSPolicyRequired()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs
             {
@@ -2344,7 +2344,7 @@ public async Task TestAuthenticatorAssertionBSPolicyDisallow()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs
             {
@@ -2421,7 +2421,7 @@ public async Task TestAuthenticatorAssertionStoredPublicKeyMissing()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs()
             {
@@ -2497,7 +2497,7 @@ public async Task TestAuthenticatorAssertionInvalidSignature()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs()
             {
@@ -2580,7 +2580,7 @@ public async Task TestAuthenticatorAssertionSignCountSignature()
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs()
             {
diff --git a/Tests/Fido2.Tests/ExistingU2fRegistrationDataTests.cs b/Tests/Fido2.Tests/ExistingU2fRegistrationDataTests.cs
index 6097498e..f03a60fb 100644
--- a/Tests/Fido2.Tests/ExistingU2fRegistrationDataTests.cs
+++ b/Tests/Fido2.Tests/ExistingU2fRegistrationDataTests.cs
@@ -14,7 +14,8 @@ public async Task TestFido2AssertionWithExistingU2fRegistrationWithAppId()
     {
         // u2f registration with appId
         var appId = "https://localhost:44336";
-        var keyHandleData = Base64Url.DecodeFromChars("2uzGTqu9XGoDQpRBhkv3qDYWzEEZrDjOHT94fHe3J9VXl6KpaY6jL1C4gCAVSBCWZejOn-EYSyXfiG7RDQqgKw");
+        var keyHandleB64Data = "2uzGTqu9XGoDQpRBhkv3qDYWzEEZrDjOHT94fHe3J9VXl6KpaY6jL1C4gCAVSBCWZejOn-EYSyXfiG7RDQqgKw";
+        var keyHandleData = Base64Url.DecodeFromChars(keyHandleB64Data);
         var publicKeyData = Base64Url.DecodeFromChars("BEKJkJiDzo8wlrYbAHmyz5a5vShbkStO58ZO7F-hy4fvBp6TowCZoV2dNGcxIN1yT18799bb_WuP0Yq_DSv5a-U");
 
         //key as cbor
@@ -36,7 +37,7 @@ public async Task TestFido2AssertionWithExistingU2fRegistrationWithAppId()
 
         var authResponse = new AuthenticatorAssertionRawResponse
         {
-            Id = keyHandleData,
+            Id = keyHandleB64Data,
             RawId = keyHandleData,
             Type = PublicKeyCredentialType.PublicKey,
             ClientExtensionResults = new AuthenticationExtensionsClientOutputs
diff --git a/Tests/Fido2.Tests/Fido2Tests.cs b/Tests/Fido2.Tests/Fido2Tests.cs
index c2b51bf2..e9b9b250 100644
--- a/Tests/Fido2.Tests/Fido2Tests.cs
+++ b/Tests/Fido2.Tests/Fido2Tests.cs
@@ -169,7 +169,7 @@ public async Task<RegisteredPublicKeyCredential> MakeAttestationResponseAsync()
             var attestationResponse = new AuthenticatorAttestationRawResponse
             {
                 Type = PublicKeyCredentialType.PublicKey,
-                Id = [0xf1, 0xd0],
+                Id = "8dA",
                 RawId = [0xf1, 0xd0],
                 Response = new AuthenticatorAttestationRawResponse.AttestationResponse
                 {
@@ -987,7 +987,7 @@ internal static async Task<VerifyAssertionResult> MakeAssertionResponseAsync(
         {
             Response = assertion,
             Type = PublicKeyCredentialType.PublicKey,
-            Id = [0xf1, 0xd0],
+            Id = "8dA",
             RawId = [0xf1, 0xd0],
         };
         IsUserHandleOwnerOfCredentialIdAsync callback = (args, cancellationToken) =>