diff --git a/Userland/Libraries/LibTextCodec/Decoder.cpp b/Userland/Libraries/LibTextCodec/Decoder.cpp
index 8cbc68df01..7eb089c962 100644
--- a/Userland/Libraries/LibTextCodec/Decoder.cpp
+++ b/Userland/Libraries/LibTextCodec/Decoder.cpp
@@ -162,8 +162,7 @@ String get_standardized_encoding(const String& encoding)
 
 bool is_standardized_encoding(const String& encoding)
 {
-    auto lowercase_encoding = encoding.to_lowercase();
-    return lowercase_encoding.is_one_of("utf-8", "ibm666", "iso-8859-2", "iso-8859-3", "iso-8859-4", "iso-8859-5", "iso-8859-6", "iso-8859-7", "iso-8859-8", "iso-8859-8-I", "iso-8859-10", "iso-8859-13", "iso-8859-14", "iso-8859-15", "iso-8859-16", "koi8-r", "koi8-u", "macintosh", "windows-874", "windows-1250", "windows-1251", "windows-1252", "windows-1253", "windows-1254", "windows-1255", "windows-1256", "windows-1257", "windows-1258", "x-mac-cyrillic", "gbk", "gb18030", "big5", "euc-jp", "iso-2022-JP", "shift_jis", "euc-kr", "replacement", "utf-16be", "utf-16le", "x-user-defined");
+    return encoding.equals_ignoring_case(get_standardized_encoding(encoding));
 }
 
 String UTF8Decoder::to_utf8(const StringView& input)