diff --git a/sim/web/main.go b/sim/web/main.go
index a3c68e6466..808961e077 100644
--- a/sim/web/main.go
+++ b/sim/web/main.go
@@ -45,7 +45,7 @@ func main() {
 	var useFS = flag.Bool("usefs", false, "Use local file system for client files. Set to true during development.")
 	var wasm = flag.Bool("wasm", false, "Use wasm for sim instead of web server apis. Can only be used with usefs=true")
 	var simName = flag.String("sim", "", "Name of simulator to launch (ex: balance_druid, elemental_shaman, etc)")
-	var host = flag.String("host", ":3333", "URL to host the interface on.")
+	var host = flag.String("host", "localhost:3333", "URL to host the interface on.")
 	var launch = flag.Bool("launch", true, "auto launch browser")
 	var skipVersionCheck = flag.Bool("nvc", false, "set true to skip version check")