diff --git a/content/reference/compose-file/services.md b/content/reference/compose-file/services.md
index 1e21cbde7962..11b6c1170fd6 100644
--- a/content/reference/compose-file/services.md
+++ b/content/reference/compose-file/services.md
@@ -1752,7 +1752,7 @@ services:
         target: server.cert
         uid: "103"
         gid: "103"
-        mode: "0440"
+        mode: "0o440"
 secrets:
   server-certificate:
     file: ./server.cert