diff --git a/src/compiler/crystal/tools/playground/server.cr b/src/compiler/crystal/tools/playground/server.cr
index 228e1e5b1d70..e0f7482d4e92 100644
--- a/src/compiler/crystal/tools/playground/server.cr
+++ b/src/compiler/crystal/tools/playground/server.cr
@@ -537,7 +537,7 @@ module Crystal::Playground
 
     private def accept_request?(origin)
       case @host
-      when nil
+      when nil, "localhost", "127.0.0.1"
         origin == "http://127.0.0.1:#{@port}" || origin == "http://localhost:#{@port}"
       when "0.0.0.0"
         true