diff --git a/test/scoped_temp_dir_win.cc b/test/scoped_temp_dir_win.cc
index ab4ff957..8031921c 100644
--- a/test/scoped_temp_dir_win.cc
+++ b/test/scoped_temp_dir_win.cc
@@ -64,7 +64,7 @@ base::FilePath ScopedTempDir::CreateTemporaryDirectory() {
     // the one we generate exists, keep trying another path name until we reach
     // some limit.
     base::FilePath path_to_create = GenerateCandidateName();
-    if (CreateDirectory(path_to_create.value().c_str(), NULL))
+    if (CreateDirectory(path_to_create.value().c_str(), nullptr))
       return path_to_create;
   }
 
diff --git a/util/file/file_io_win.cc b/util/file/file_io_win.cc
index 7428034a..111a8da2 100644
--- a/util/file/file_io_win.cc
+++ b/util/file/file_io_win.cc
@@ -28,7 +28,7 @@ bool IsSocketHandle(HANDLE file) {
     // FILE_TYPE_PIPE means that it's a socket, a named pipe, or an anonymous
     // pipe. If we are unable to retrieve the pipe information, we know it's a
     // socket.
-    return !GetNamedPipeInfo(file, NULL, NULL, NULL, NULL);
+    return !GetNamedPipeInfo(file, nullptr, nullptr, nullptr, nullptr);
   }
   return false;
 }
diff --git a/util/net/http_transport_win.cc b/util/net/http_transport_win.cc
index 09876882..06ecc4f3 100644
--- a/util/net/http_transport_win.cc
+++ b/util/net/http_transport_win.cc
@@ -97,7 +97,7 @@ std::string WinHttpMessage(const char* extra) {
                              0,
                              msgbuf,
                              static_cast<DWORD>(base::size(msgbuf)),
-                             NULL);
+                             nullptr);
   if (!len) {
     return base::StringPrintf("%s: error 0x%lx while retrieving error 0x%lx",
                               extra,