diff --git a/app/models/cluster.rb b/app/models/cluster.rb
index f1ffa9d..88f9ce9 100644
--- a/app/models/cluster.rb
+++ b/app/models/cluster.rb
@@ -13,6 +13,7 @@ class Cluster < ApplicationRecord
   validates_presence_of :name
   validates_presence_of :endpoint
   validates_presence_of :secrets
+  validates_format_of :name, with: /\A[a-z0-9-]+\z/, message: "may only contain lowercase letters, numbers and dashes"
   validate :validate_secrets_yaml
   validate :validate_endpoint_url