diff --git a/client/crashpad_client_win.cc b/client/crashpad_client_win.cc
index f9d8e129..c06b7896 100644
--- a/client/crashpad_client_win.cc
+++ b/client/crashpad_client_win.cc
@@ -277,7 +277,7 @@ void AddUint64(std::vector<unsigned char>* data_vector, uint64_t data) {
 void CreatePipe(std::wstring* pipe_name, ScopedFileHANDLE* pipe_instance) {
   int tries = 5;
   std::string pipe_name_base =
-      base::StringPrintf("\\\\.\\pipe\\crashpad_%d_", GetCurrentProcessId());
+      base::StringPrintf("\\\\.\\pipe\\crashpad_%lu_", GetCurrentProcessId());
   do {
     *pipe_name = base::UTF8ToUTF16(pipe_name_base + RandomString());
 
diff --git a/snapshot/win/system_snapshot_win.cc b/snapshot/win/system_snapshot_win.cc
index 4e4114ff..74f34a7e 100644
--- a/snapshot/win/system_snapshot_win.cc
+++ b/snapshot/win/system_snapshot_win.cc
@@ -106,7 +106,7 @@ void SystemSnapshotWin::Initialize(ProcessReaderWin* process_reader) {
     os_version_major_ = ffi.dwFileVersionMS >> 16;
     os_version_minor_ = ffi.dwFileVersionMS & 0xffff;
     os_version_bugfix_ = ffi.dwFileVersionLS >> 16;
-    os_version_build_ = base::StringPrintf("%u", ffi.dwFileVersionLS & 0xffff);
+    os_version_build_ = base::StringPrintf("%lu", ffi.dwFileVersionLS & 0xffff);
     os_version_full_ = base::StringPrintf(
         "%s %u.%u.%u.%s%s",
         os_name.c_str(),
diff --git a/util/net/http_transport_win.cc b/util/net/http_transport_win.cc
index 27cd4048..9698df30 100644
--- a/util/net/http_transport_win.cc
+++ b/util/net/http_transport_win.cc
@@ -47,7 +47,7 @@ std::string UserAgent() {
 
   VS_FIXEDFILEINFO version;
   if (GetModuleVersionAndType(base::FilePath(kWinHttpDll), &version)) {
-    user_agent.append(base::StringPrintf("/%u.%u.%u.%u",
+    user_agent.append(base::StringPrintf("/%lu.%lu.%lu.%lu",
                                          version.dwFileVersionMS >> 16,
                                          version.dwFileVersionMS & 0xffff,
                                          version.dwFileVersionLS >> 16,
@@ -56,7 +56,7 @@ std::string UserAgent() {
 
   if (GetModuleVersionAndType(base::FilePath(L"kernel32.dll"), &version) &&
       (version.dwFileOS & VOS_NT_WINDOWS32) == VOS_NT_WINDOWS32) {
-    user_agent.append(base::StringPrintf(" Windows_NT/%u.%u.%u.%u (",
+    user_agent.append(base::StringPrintf(" Windows_NT/%lu.%lu.%lu.%lu (",
                                          version.dwFileVersionMS >> 16,
                                          version.dwFileVersionMS & 0xffff,
                                          version.dwFileVersionLS >> 16,
@@ -96,12 +96,12 @@ std::string WinHttpMessage(const char* extra) {
                              arraysize(msgbuf),
                              NULL);
   if (!len) {
-    return base::StringPrintf("%s: error 0x%x while retrieving error 0x%x",
+    return base::StringPrintf("%s: error 0x%lx while retrieving error 0x%lx",
                               extra,
                               GetLastError(),
                               error_code);
   }
-  return base::StringPrintf("%s: %s (0x%x)", extra, msgbuf, error_code);
+  return base::StringPrintf("%s: %s (0x%lx)", extra, msgbuf, error_code);
 }
 
 struct ScopedHINTERNETTraits {
@@ -371,7 +371,7 @@ bool HTTPTransportWin::ExecuteSynchronously(std::string* response_body) {
   }
 
   if (status_code != 200) {
-    LOG(ERROR) << base::StringPrintf("HTTP status %d", status_code);
+    LOG(ERROR) << base::StringPrintf("HTTP status %lu", status_code);
     return false;
   }
 
diff --git a/util/win/ntstatus_logging.cc b/util/win/ntstatus_logging.cc
index 4c243cc5..e06fe248 100644
--- a/util/win/ntstatus_logging.cc
+++ b/util/win/ntstatus_logging.cc
@@ -34,7 +34,7 @@ std::string FormatNtstatus(DWORD ntstatus) {
   if (len) {
     return msgbuf;
   } else {
-    return base::StringPrintf("<failed to retrieve error message (0x%x)>",
+    return base::StringPrintf("<failed to retrieve error message (0x%lx)>",
                               GetLastError());
   }
 }
@@ -63,7 +63,7 @@ NtstatusLogMessage::NtstatusLogMessage(
 
 NtstatusLogMessage::~NtstatusLogMessage() {
   stream() << ": " << FormatNtstatus(ntstatus_)
-           << base::StringPrintf(" (0x%08x)", ntstatus_);
+           << base::StringPrintf(" (0x%08lx)", ntstatus_);
 }
 
 }  // namespace logging