diff --git a/src/core/net/dns_headers.cpp b/src/core/net/dns_headers.cpp
index 1fbe68dd9..74a73b7e3 100644
--- a/src/core/net/dns_headers.cpp
+++ b/src/core/net/dns_headers.cpp
@@ -128,8 +128,6 @@ otError Name::AppendMultipleLabels(const char *aLabels, Message &aMessage)
 
     do
     {
-        VerifyOrExit(index < kMaxLength, error = OT_ERROR_INVALID_ARGS);
-
         ch = aLabels[index];
 
         if ((ch == kNullChar) || (ch == kLabelSeperatorChar))
@@ -149,6 +147,7 @@ otError Name::AppendMultipleLabels(const char *aLabels, Message &aMessage)
                 ExitNow();
             }
 
+            VerifyOrExit(index + 1 < kMaxEncodedLength, error = OT_ERROR_INVALID_ARGS);
             SuccessOrExit(error = AppendLabel(&aLabels[labelStartIndex], labelLength, aMessage));
 
             labelStartIndex = index + 1;
diff --git a/src/core/net/dns_headers.hpp b/src/core/net/dns_headers.hpp
index bf127d055..ff3208ffd 100644
--- a/src/core/net/dns_headers.hpp
+++ b/src/core/net/dns_headers.hpp
@@ -487,8 +487,9 @@ class Name
 public:
     enum : uint8_t
     {
-        kMaxLabelLength = 63,  ///< Max number of characters in a label.
-        kMaxLength      = 255, ///< Max number of characters in a name.
+        kMaxLabelLength   = 63,  ///< Max number of characters in a label.
+        kMaxLength        = 254, ///< Max number of characters in a name.
+        kMaxEncodedLength = 255, ///< Max length of an encoded name.
     };
 
     /**
diff --git a/tests/unit/test_dns.cpp b/tests/unit/test_dns.cpp
index 742b5c8e5..252623771 100644
--- a/tests/unit/test_dns.cpp
+++ b/tests/unit/test_dns.cpp
@@ -88,6 +88,18 @@ void TestDnsName(void)
         {nullptr, sizeof(kEncodedName4), kEncodedName4, kLabels4, "."},
     };
 
+    static const char *kMaxLengthNames[] = {
+        "HereIsSomeoneHidden.MyHoldFromMeTaken.FromSelfHasMeDriven.MyLeadFromMeTaken."
+        "HereIsSomeoneHidden.AsLifeSweeterThanLife.TakesMeToGardenOfSoul.MyFortFromMeTaken."
+        "HereIsSomeoneHidden.LikeSugarInSugarCane.ASweetSugarTrader.MyShopFromMeTaken."
+        "SorcererAndMagicia.",
+
+        "HereIsSomeoneHidden.MyHoldFromMeTaken.FromSelfHasMeDriven.MyLeadFromMeTaken."
+        "HereIsSomeoneHidden.AsLifeSweeterThanLife.TakesMeToGardenOfSoul.MyFortFromMeTaken."
+        "HereIsSomeoneHidden.LikeSugarInSugarCane.ASweetSugarTrader.MyShopFromMeTaken."
+        "SorcererAndMagicia",
+    };
+
     static const char *kInvalidNames[] = {
         "foo..bar",
         "..",
@@ -104,6 +116,19 @@ void TestDnsName(void)
         "SorcererAndMagician.NoEyesCanEverSee.AnArtfulConjurer.MySenseFromMeTaken."
         "MyEyesWillNeverSee.BeautiesOfTheWholeWorld.BeholdWhoseVisionFine.MySightFromMeTaken"
         "PoemByRumiMolana",
+
+        // Long name of 255 characters which ends with a dot
+        "HereIsSomeoneHidden.MyHoldFromMeTaken.FromSelfHasMeDriven.MyLeadFromMeTaken."
+        "HereIsSomeoneHidden.AsLifeSweeterThanLife.TakesMeToGardenOfSoul.MyFortFromMeTaken."
+        "HereIsSomeoneHidden.LikeSugarInSugarCane.ASweetSugarTrader.MyShopFromMeTaken."
+        "SorcererAndMagician.",
+
+        // Long name of 254 characters which does not end with a dot
+        "HereIsSomeoneHidden.MyHoldFromMeTaken.FromSelfHasMeDriven.MyLeadFromMeTaken."
+        "HereIsSomeoneHidden.AsLifeSweeterThanLife.TakesMeToGardenOfSoul.MyFortFromMeTaken."
+        "HereIsSomeoneHidden.LikeSugarInSugarCane.ASweetSugarTrader.MyShopFromMeTaken."
+        "SorcererAndMagician",
+
     };
 
     printf("================================================================\n");
@@ -177,6 +202,28 @@ void TestDnsName(void)
                      "Name::ReadName() did not fail with too small name buffer size");
     }
 
+    printf("----------------------------------------------------------------\n");
+    printf("Max length names:\n");
+
+    for (const char *&maxLengthName : kMaxLengthNames)
+    {
+        if (maxLengthName[strlen(maxLengthName) - 1] == '.')
+        {
+            VerifyOrQuit(strlen(maxLengthName) == Dns::Name::kMaxLength, "invalid max length string");
+        }
+        else
+        {
+            VerifyOrQuit(strlen(maxLengthName) == Dns::Name::kMaxLength - 1, "invalid max length string");
+        }
+
+        IgnoreError(message->SetLength(0));
+
+        printf("\"%s\"\n", maxLengthName);
+
+        VerifyOrQuit(Dns::Name::AppendName(maxLengthName, *message) == OT_ERROR_NONE,
+                     "Name::AppendName() failed with max length name");
+    }
+
     printf("----------------------------------------------------------------\n");
     printf("Invalid names:\n");