diff --git a/src/node_javascript.cc b/src/node_javascript.cc
index 6159cfede93810..5ba6e1d0a276f3 100644
--- a/src/node_javascript.cc
+++ b/src/node_javascript.cc
@@ -20,7 +20,7 @@ using v8::String;
 Local<String> MainSource(Environment* env) {
   return String::NewFromUtf8(
       env->isolate(), reinterpret_cast<const char*>(node_native),
-      NewStringType::kNormal, sizeof(node_native) - 1).ToLocalChecked();
+      NewStringType::kNormal, sizeof(node_native)).ToLocalChecked();
 }
 
 void DefineJavaScript(Environment* env, Local<Object> target) {
diff --git a/tools/js2c.py b/tools/js2c.py
index 9c5878a66818eb..761e80be59f76e 100755
--- a/tools/js2c.py
+++ b/tools/js2c.py
@@ -42,7 +42,7 @@
 
 
 def ToCArray(filename, lines):
-  return ','.join(str(ord(c)) for c in lines + '\0')
+  return ','.join(str(ord(c)) for c in lines)
 
 
 def CompressScript(lines, do_jsmin):
@@ -221,7 +221,7 @@ def ReadMacros(lines):
 
 
 NATIVE_DECLARATION = """\
-  { "%(id)s", %(escaped_id)s_native, sizeof(%(escaped_id)s_native)-1 },
+  { "%(id)s", %(escaped_id)s_native, sizeof(%(escaped_id)s_native) },
 """
 
 SOURCE_DECLARATION = """\