diff --git a/apps/openmw/mwgui/mapwindow.cpp b/apps/openmw/mwgui/mapwindow.cpp
index 7f1ecd89d8..485e7f7ed0 100644
--- a/apps/openmw/mwgui/mapwindow.cpp
+++ b/apps/openmw/mwgui/mapwindow.cpp
@@ -36,7 +36,7 @@ namespace
 {
 
     const int cellSize = Constants::CellSizeInUnits;
-    constexpr float speed = 1.08;   //the zoom speed, it should be greater than 1
+    constexpr float speed = 1.08f;   //the zoom speed, it should be greater than 1
 
     enum LocalMapWidgetDepth
     {