diff --git a/v2rayN/ServiceLib.Tests/Fmt/AnytlsFmtTests.cs b/v2rayN/ServiceLib.Tests/Fmt/AnytlsFmtTests.cs
new file mode 100644
index 00000000..f3cc1354
--- /dev/null
+++ b/v2rayN/ServiceLib.Tests/Fmt/AnytlsFmtTests.cs
@@ -0,0 +1,47 @@
+namespace ServiceLib.Tests.Fmt;
+
+public class AnytlsFmtTests
+{
+    // "服务器的地址和可选端口。如果省略端口，则默认为 443。" (the port is optional and defaults to 443)
+    // -- https://github.com/anytls/anytls-go/blob/main/docs/uri_scheme.md
+    // The first two cases are the examples given there.
+    [Test]
+    [Arguments("anytls://letmein@example.com/?sni=real.example.com")]
+    [Arguments("anytls://letmein@example.com/?sni=127.0.0.1&insecure=1")]
+    [Arguments("anytls://letmein@example.com")]
+    [Arguments("anytls://letmein@example.com:/")]
+    public async Task ResolveConfig_WithoutPort_ShouldDefaultTo443(string shareUri)
+    {
+        var resolved = FmtHandler.ResolveConfig(shareUri, out var msg);
+
+        await resolved.Should().NotBeNull().Because($"uri: {shareUri}, msg: {msg}");
+        await resolved!.ConfigType.Should().BeEqualTo(EConfigType.Anytls);
+        await resolved.Address.Should().BeEqualTo("example.com");
+        await resolved.Port.Should().BeEqualTo(443);
+        await resolved.Password.Should().BeEqualTo("letmein");
+        await resolved.IsValid().Should().BeTrue();
+    }
+
+    [Test]
+    public async Task ResolveConfig_WithExplicitPort_ShouldKeepIt()
+    {
+        // The third example from the URI scheme document.
+        const string shareUri = "anytls://0fdf77d7-d4ba-455e-9ed9-a98dd6d5489a@[2409:8a71:6a00:1953::615]:8964/?insecure=1";
+
+        var resolved = FmtHandler.ResolveConfig(shareUri, out var msg);
+
+        await resolved.Should().NotBeNull().Because($"uri: {shareUri}, msg: {msg}");
+        await resolved!.Address.Should().BeEqualTo("2409:8a71:6a00:1953::615");
+        await resolved.Port.Should().BeEqualTo(8964);
+    }
+
+    [Test]
+    public async Task ResolveConfig_WithExplicitZeroPort_ShouldNotApplyTheDefault()
+    {
+        var resolved = FmtHandler.ResolveConfig("anytls://letmein@example.com:0/", out _);
+
+        await resolved.Should().NotBeNull();
+        await resolved!.Port.Should().BeEqualTo(0);
+        await resolved.IsValid().Should().BeFalse();
+    }
+}
diff --git a/v2rayN/ServiceLib.Tests/Fmt/NaiveFmtTests.cs b/v2rayN/ServiceLib.Tests/Fmt/NaiveFmtTests.cs
new file mode 100644
index 00000000..1d1f4694
--- /dev/null
+++ b/v2rayN/ServiceLib.Tests/Fmt/NaiveFmtTests.cs
@@ -0,0 +1,44 @@
+namespace ServiceLib.Tests.Fmt;
+
+public class NaiveFmtTests
+{
+    // "port can be omitted if it's 443" -- https://gist.github.com/DuckSoft/ca03913b0a26fc77a1da4d01cc6ab2f1
+    // The first two cases are examples given there; none of its examples carries a port.
+    [Test]
+    [Arguments("naive+https://what:happened@test.someone.cf?padding=false#Naive!", false)]
+    [Arguments("naive+quic://manhole:114514@quic.test.me", true)]
+    [Arguments("naive+https://what:happened@test.someone.cf/", false)]
+    [Arguments("naive+https://what:happened@test.someone.cf:/", false)]
+    public async Task ResolveConfig_WithoutPort_ShouldDefaultTo443(string shareUri, bool quic)
+    {
+        var resolved = FmtHandler.ResolveConfig(shareUri, out var msg);
+
+        await resolved.Should().NotBeNull().Because($"uri: {shareUri}, msg: {msg}");
+        await resolved!.ConfigType.Should().BeEqualTo(EConfigType.Naive);
+        await resolved.Port.Should().BeEqualTo(443);
+        await (resolved.GetProtocolExtra().NaiveQuic == true).Should().BeEqualTo(quic);
+        await resolved.IsValid().Should().BeTrue();
+    }
+
+    [Test]
+    public async Task ResolveConfig_WithExplicitPort_ShouldKeepIt()
+    {
+        var resolved = FmtHandler.ResolveConfig("naive+https://what:happened@test.someone.cf:8443", out _);
+
+        await resolved.Should().NotBeNull();
+        await resolved!.Address.Should().BeEqualTo("test.someone.cf");
+        await resolved.Port.Should().BeEqualTo(8443);
+        await resolved.Username.Should().BeEqualTo("what");
+        await resolved.Password.Should().BeEqualTo("happened");
+    }
+
+    [Test]
+    public async Task ResolveConfig_WithExplicitZeroPort_ShouldNotApplyTheDefault()
+    {
+        var resolved = FmtHandler.ResolveConfig("naive+https://what:happened@test.someone.cf:0", out _);
+
+        await resolved.Should().NotBeNull();
+        await resolved!.Port.Should().BeEqualTo(0);
+        await resolved.IsValid().Should().BeFalse();
+    }
+}
diff --git a/v2rayN/ServiceLib/Handler/Fmt/AnytlsFmt.cs b/v2rayN/ServiceLib/Handler/Fmt/AnytlsFmt.cs
index 4ea6a0eb..6853a6f4 100644
--- a/v2rayN/ServiceLib/Handler/Fmt/AnytlsFmt.cs
+++ b/v2rayN/ServiceLib/Handler/Fmt/AnytlsFmt.cs
@@ -17,7 +17,10 @@ public class AnytlsFmt : BaseFmt
             ConfigType = EConfigType.Anytls,
             Remarks = parsedUrl.GetComponents(UriComponents.Fragment, UriFormat.Unescaped),
             Address = parsedUrl.IdnHost,
-            Port = parsedUrl.Port,
+            // The URI scheme makes the port optional and defaults it to 443
+            // (https://github.com/anytls/anytls-go/blob/main/docs/uri_scheme.md). Uri.Port answers
+            // -1 for an unregistered scheme carrying no port; an explicit ":0" stays 0.
+            Port = parsedUrl.Port == -1 ? 443 : parsedUrl.Port,
         };
         var rawUserInfo = Utils.UrlDecode(parsedUrl.UserInfo);
         item.Password = rawUserInfo;
diff --git a/v2rayN/ServiceLib/Handler/Fmt/NaiveFmt.cs b/v2rayN/ServiceLib/Handler/Fmt/NaiveFmt.cs
index 5792472b..5349b205 100644
--- a/v2rayN/ServiceLib/Handler/Fmt/NaiveFmt.cs
+++ b/v2rayN/ServiceLib/Handler/Fmt/NaiveFmt.cs
@@ -17,7 +17,10 @@ public class NaiveFmt : BaseFmt
             ConfigType = EConfigType.Naive,
             Remarks = parsedUrl.GetComponents(UriComponents.Fragment, UriFormat.Unescaped),
             Address = parsedUrl.IdnHost,
-            Port = parsedUrl.Port,
+            // naive+https:// and naive+quic:// links leave the port out when it is 443
+            // (https://gist.github.com/DuckSoft/ca03913b0a26fc77a1da4d01cc6ab2f1). Uri.Port answers
+            // -1 for an unregistered scheme carrying no port; an explicit ":0" stays 0.
+            Port = parsedUrl.Port == -1 ? 443 : parsedUrl.Port,
         };
         var protocolExtra = item.GetProtocolExtra();
         if (parsedUrl.Scheme.Contains("quic"))