diff --git a/src/openrct2/windows/editor_inventions_list.cpp b/src/openrct2/windows/editor_inventions_list.cpp
index 5f582aecf1..d0e068cd29 100644
--- a/src/openrct2/windows/editor_inventions_list.cpp
+++ b/src/openrct2/windows/editor_inventions_list.cpp
@@ -270,7 +270,7 @@ extern rct_object_entry RequiredSelectedObjects[7];
  */
 static void research_scenery_sets_setup(){
 
-    for (sint32 i = 0; i < Util::CountOf(RequiredSelectedObjects); i++) {
+    for (size_t i = 0; i < Util::CountOf(RequiredSelectedObjects); i++) {
         rct_object_entry * object = &RequiredSelectedObjects[i];
 
         uint8 entry_type, entry_index;
diff --git a/src/openrct2/windows/music_credits.cpp b/src/openrct2/windows/music_credits.cpp
index 7c87af68b5..06290dfb04 100644
--- a/src/openrct2/windows/music_credits.cpp
+++ b/src/openrct2/windows/music_credits.cpp
@@ -193,7 +193,7 @@ static void window_music_credits_scrollpaint(rct_window *w, rct_drawpixelinfo *d
 
     sint32 y = 2;
 
-    for (sint32 i = 0; i < Util::CountOf(music_credits); i++) {
+    for (size_t i = 0; i < Util::CountOf(music_credits); i++) {
         gfx_draw_string_centred(dpi, music_credits[i], x, y, COLOUR_BLACK, NULL);
         y += 10;
     }
@@ -208,7 +208,7 @@ static void window_music_credits_scrollpaint(rct_window *w, rct_drawpixelinfo *d
     gfx_fill_rect_inset(dpi, 4, y, 484, y+1, w->colours[1], INSET_RECT_FLAG_BORDER_INSET);
     y += 11;
 
-    for (sint32 i = 0; i < Util::CountOf(music_credits_rct2); i++) {
+    for (size_t i = 0; i < Util::CountOf(music_credits_rct2); i++) {
         gfx_draw_string_centred(dpi, music_credits_rct2[i], x, y, COLOUR_BLACK, NULL);
         y += 10;
     }
diff --git a/src/openrct2/windows/news_options.cpp b/src/openrct2/windows/news_options.cpp
index 9eb7f47a25..4bd7b2d01a 100644
--- a/src/openrct2/windows/news_options.cpp
+++ b/src/openrct2/windows/news_options.cpp
@@ -172,7 +172,7 @@ static void window_news_options_mouseup(rct_window *w, rct_widgetindex widgetInd
         sint32 checkBoxIndex = widgetIndex - WIDX_CHECKBOX_0;
         if (checkBoxIndex >= 0) {
             sint32 matchIndex = 0;
-            for (sint32 i = 0; i < Util::CountOf(NewsItemOptionDefinitions); i++) {
+            for (size_t i = 0; i < Util::CountOf(NewsItemOptionDefinitions); i++) {
                 const notification_def *ndef = &NewsItemOptionDefinitions[i];
                 if (ndef->category != w->page) continue;
 
@@ -214,7 +214,7 @@ static void window_news_options_invalidate(rct_window *w)
 
     sint32 checkboxWidgetIndex = WIDX_CHECKBOX_0;
     rct_widget *checkboxWidget = &w->widgets[checkboxWidgetIndex];
-    for (sint32 i = 0; i < Util::CountOf(NewsItemOptionDefinitions); i++) {
+    for (size_t i = 0; i < Util::CountOf(NewsItemOptionDefinitions); i++) {
         const notification_def *ndef = &NewsItemOptionDefinitions[i];
         if (ndef->category != w->page) continue;
 
diff --git a/src/openrct2/windows/ride.cpp b/src/openrct2/windows/ride.cpp
index 7f07ce4bd6..aafb0f0a48 100644
--- a/src/openrct2/windows/ride.cpp
+++ b/src/openrct2/windows/ride.cpp
@@ -4822,8 +4822,8 @@ static void window_ride_music_mousedown(rct_window *w, rct_widgetindex widgetInd
     if (ride->type == RIDE_TYPE_MERRY_GO_ROUND) {
         window_ride_current_music_style_order[numItems++] = MUSIC_STYLE_FAIRGROUND_ORGAN;
     } else {
-        for (i = 0; i < Util::CountOf(MusicStyleOrder); i++)
-            window_ride_current_music_style_order[numItems++] = MusicStyleOrder[i];
+        for (size_t n = 0; n < Util::CountOf(MusicStyleOrder); n++)
+            window_ride_current_music_style_order[numItems++] = MusicStyleOrder[n];
 
         if (gRideMusicInfoList[36]->length != 0)
             window_ride_current_music_style_order[numItems++] = MUSIC_STYLE_CUSTOM_MUSIC_1;
diff --git a/src/openrct2/windows/ride_list.cpp b/src/openrct2/windows/ride_list.cpp
index b23502da2c..bd6307ae3b 100644
--- a/src/openrct2/windows/ride_list.cpp
+++ b/src/openrct2/windows/ride_list.cpp
@@ -378,7 +378,7 @@ static void window_ride_list_dropdown(rct_window *w, rct_widgetindex widgetIndex
 
         sint32 informationType = INFORMATION_TYPE_STATUS;
         uint32 arg = (uint32)gDropdownItemsArgs[dropdownIndex];
-        for (sint32 i = 0; i < Util::CountOf(ride_info_type_string_mapping); i++) {
+        for (size_t i = 0; i < Util::CountOf(ride_info_type_string_mapping); i++) {
             if (arg == ride_info_type_string_mapping[i]) {
                 informationType = i;
             }
diff --git a/src/openrct2/windows/top_toolbar.cpp b/src/openrct2/windows/top_toolbar.cpp
index 4d5d9bd77b..e12fd1873f 100644
--- a/src/openrct2/windows/top_toolbar.cpp
+++ b/src/openrct2/windows/top_toolbar.cpp
@@ -748,7 +748,7 @@ static void window_top_toolbar_invalidate(rct_window *w)
     // Align left hand side toolbar buttons
     firstAlignment = 1;
     x = 0;
-    for (sint32 i = 0; i < Util::CountOf(left_aligned_widgets_order); ++i) {
+    for (size_t i = 0; i < Util::CountOf(left_aligned_widgets_order); ++i) {
         widgetIndex = left_aligned_widgets_order[i];
         widget = &window_top_toolbar_widgets[widgetIndex];
         if (widget->type == WWT_EMPTY && widgetIndex != WIDX_SEPARATOR)
@@ -769,7 +769,7 @@ static void window_top_toolbar_invalidate(rct_window *w)
     sint32 screenWidth = context_get_width();
     firstAlignment = 1;
     x = Math::Max(640, screenWidth);
-    for (sint32 i = 0; i < Util::CountOf(right_aligned_widgets_order); ++i) {
+    for (size_t i = 0; i < Util::CountOf(right_aligned_widgets_order); ++i) {
         widgetIndex = right_aligned_widgets_order[i];
         widget = &window_top_toolbar_widgets[widgetIndex];
         if (widget->type == WWT_EMPTY && widgetIndex != WIDX_SEPARATOR)