diff --git a/UI/window-basic-main.cpp b/UI/window-basic-main.cpp
index e8dc0fe84..1f02f6f10 100644
--- a/UI/window-basic-main.cpp
+++ b/UI/window-basic-main.cpp
@@ -1200,7 +1200,7 @@ bool OBSBasic::InitBasicConfigDefaults()
 	config_set_default_string(basicConfig, "SimpleOutput", "FilePath",
 				  GetDefaultVideoSavePath().c_str());
 	config_set_default_string(basicConfig, "SimpleOutput", "RecFormat",
-				  "flv");
+				  "mkv");
 	config_set_default_uint(basicConfig, "SimpleOutput", "VBitrate", 2500);
 	config_set_default_uint(basicConfig, "SimpleOutput", "ABitrate", 160);
 	config_set_default_bool(basicConfig, "SimpleOutput", "UseAdvanced",
@@ -1229,7 +1229,7 @@ bool OBSBasic::InitBasicConfigDefaults()
 
 	config_set_default_string(basicConfig, "AdvOut", "RecFilePath",
 				  GetDefaultVideoSavePath().c_str());
-	config_set_default_string(basicConfig, "AdvOut", "RecFormat", "flv");
+	config_set_default_string(basicConfig, "AdvOut", "RecFormat", "mkv");
 	config_set_default_bool(basicConfig, "AdvOut", "RecUseRescale", false);
 	config_set_default_uint(basicConfig, "AdvOut", "RecTracks", (1 << 0));
 	config_set_default_string(basicConfig, "AdvOut", "RecEncoder", "none");