diff --git a/Tests/LibWeb/Text/expected/URL/invalid-urls.txt b/Tests/LibWeb/Text/expected/URL/invalid-urls.txt
index 7ffbe3d1b7b..b58cdb108e6 100644
--- a/Tests/LibWeb/Text/expected/URL/invalid-urls.txt
+++ b/Tests/LibWeb/Text/expected/URL/invalid-urls.txt
@@ -1,2 +1,4 @@
 new URL('file://xn--/p', undefined)
 error creating URL: 'TypeError: Invalid URL'
+new URL('http://0xffffffff1', undefined)
+error creating URL: 'TypeError: Invalid URL'
diff --git a/Tests/LibWeb/Text/input/URL/invalid-urls.html b/Tests/LibWeb/Text/input/URL/invalid-urls.html
index b8f73c9fece..bb0e774765f 100644
--- a/Tests/LibWeb/Text/input/URL/invalid-urls.html
+++ b/Tests/LibWeb/Text/input/URL/invalid-urls.html
@@ -3,6 +3,7 @@
     test(() => {
         const urls = [
             { input: 'file://xn--/p' },
+            { input: 'http://0xffffffff1' },
         ];
 
         for (url of urls) {
diff --git a/Userland/Libraries/LibURL/Parser.cpp b/Userland/Libraries/LibURL/Parser.cpp
index 6a9aa801b86..f69afda01bd 100644
--- a/Userland/Libraries/LibURL/Parser.cpp
+++ b/Userland/Libraries/LibURL/Parser.cpp
@@ -583,7 +583,8 @@ static bool ends_in_a_number_checker(StringView input)
         return true;
 
     // 5. If parsing last as an IPv4 number does not return failure, then return true.
-    if (parse_ipv4_number(last).has_value())
+    // NOTE: This is equivalent to checking that last is "0X" or "0x", followed by zero or more ASCII hex digits.
+    if (last.starts_with("0x"sv, CaseSensitivity::CaseInsensitive) && all_of(last.substring_view(2), is_ascii_hex_digit))
         return true;
 
     // 6. Return false.