diff --git a/cmd/kubeadm/app/cmd/phases/init/certs.go b/cmd/kubeadm/app/cmd/phases/init/certs.go
index 9520aa8400e..3a248f5cc47 100644
--- a/cmd/kubeadm/app/cmd/phases/init/certs.go
+++ b/cmd/kubeadm/app/cmd/phases/init/certs.go
@@ -42,7 +42,7 @@ var (
 		`+cmdutil.AlphaDisclaimer), kubeadmconstants.ServiceAccountPrivateKeyName, kubeadmconstants.ServiceAccountPublicKeyName)
 
 	genericLongDesc = cmdutil.LongDesc(`
-		Generate the %[1]s, and save them into %[2]s.cert and %[2]s.key files.%[3]s
+		Generate the %[1]s, and save them into %[2]s.crt and %[2]s.key files.%[3]s
 
 		If both files already exist, kubeadm skips the generation step and existing files will be used.
 		` + cmdutil.AlphaDisclaimer)