diff --git a/AK/StringBuilder.cpp b/AK/StringBuilder.cpp
index 6c1f3040cd..aa0329a947 100644
--- a/AK/StringBuilder.cpp
+++ b/AK/StringBuilder.cpp
@@ -69,15 +69,6 @@ void StringBuilder::appendvf(const char* fmt, va_list ap)
         nullptr, fmt, ap);
 }
 
-void StringBuilder::appendf(const char* fmt, ...)
-{
-    va_list ap;
-    va_start(ap, fmt);
-    will_append(strlen(fmt));
-    appendvf(fmt, ap);
-    va_end(ap);
-}
-
 ByteBuffer StringBuilder::to_byte_buffer() const
 {
     return ByteBuffer::copy(data(), length());
diff --git a/AK/StringBuilder.h b/AK/StringBuilder.h
index b1b21b9566..e97b76b6af 100644
--- a/AK/StringBuilder.h
+++ b/AK/StringBuilder.h
@@ -26,7 +26,6 @@ public:
     void append(char);
     void append_code_point(u32);
     void append(const char*, size_t);
-    void appendf(const char*, ...) __attribute__((format(printf, 2, 3)));
     void appendvf(const char*, va_list);
 
     void append_escaped_for_json(const StringView&);