diff --git a/UI/window-basic-main.cpp b/UI/window-basic-main.cpp
index dabc30a537f0ea7bcb6f1d0ceb5238e9a96aa4ba..6db61a4839d1be9e6b09b2986e53a678f3775e8e 100644
--- a/UI/window-basic-main.cpp
+++ b/UI/window-basic-main.cpp
@@ -1193,7 +1193,7 @@ 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",
@@ -1222,7 +1222,7 @@ 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");