diff --git a/tools/base94_encoder.cc b/tools/base94_encoder.cc
index c99210f2..31cabe79 100644
--- a/tools/base94_encoder.cc
+++ b/tools/base94_encoder.cc
@@ -14,6 +14,7 @@
 
 #include <getopt.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "base/files/file_path.h"
 #include "build/build_config.h"