diff --git a/tests/unittests/request_unittest.cc b/tests/unittests/request_unittest.cc
index 92c4ae655..00836a9ab 100644
--- a/tests/unittests/request_unittest.cc
+++ b/tests/unittests/request_unittest.cc
@@ -237,7 +237,9 @@ class TypeExpectations {
   explicit TypeExpectations(bool navigation)
       : navigation_(navigation) {
     // Build the map of relevant requests.
-    for (size_t i = 0; i < sizeof(g_type_expected) / sizeof(TypeExpected); ++i) {
+    for (int i = 0;
+         i < static_cast<int>(sizeof(g_type_expected) / sizeof(TypeExpected));
+         ++i) {
       if (navigation_ && g_type_expected[i].navigation != navigation_)
         continue;
 
@@ -279,7 +281,9 @@ class TypeExpectations {
 
   // Test if all expectations have been met.
   bool IsDone(bool assert) {
-    for (size_t i = 0; i < sizeof(g_type_expected) / sizeof(TypeExpected); ++i) {
+    for (int i = 0;
+         i < static_cast<int>(sizeof(g_type_expected) / sizeof(TypeExpected));
+         ++i) {
       if (navigation_ && g_type_expected[i].navigation != navigation_)
         continue;
 
@@ -304,7 +308,9 @@ class TypeExpectations {
   int GetExpectedIndex(const std::string& file,
                        cef_transition_type_t transition_type,
                        cef_resource_type_t resource_type) {
-    for (size_t i = 0; i < sizeof(g_type_expected) / sizeof(TypeExpected); ++i) {
+    for (int i = 0;
+         i < static_cast<int>(sizeof(g_type_expected) / sizeof(TypeExpected));
+         ++i) {
       if (g_type_expected[i].file == file &&
           (!navigation_ || g_type_expected[i].navigation == navigation_) &&
           g_type_expected[i].transition_type == transition_type &&