diff --git a/app/models/wiki_page.rb b/app/models/wiki_page.rb
index a60e10863..79922b98c 100644
--- a/app/models/wiki_page.rb
+++ b/app/models/wiki_page.rb
@@ -3,14 +3,13 @@ class WikiPage < ApplicationRecord
 
   META_WIKIS = ["list_of_", "tag_group:", "pool_group:", "howto:", "about:", "help:", "template:"]
 
-  before_save :normalize_title
-  before_save :normalize_other_names
+  before_validation :normalize_title
+  before_validation :normalize_other_names
   before_save :update_dtext_links, if: :dtext_links_changed?
   after_save :create_version
 
-  validates_uniqueness_of :title, :case_sensitive => false
-  validates_presence_of :title
-  validates_presence_of :body, :unless => -> { is_deleted? || other_names.present? }
+  validates :title, tag_name: true, presence: true, uniqueness: true, if: :title_changed?
+  validates :body, presence: true, unless: -> { is_deleted? || other_names.present? }
   validate :validate_rename
   validate :validate_other_names
 
@@ -149,8 +148,7 @@ class WikiPage < ApplicationRecord
   end
 
   def self.normalize_title(title)
-    return if title.blank?
-    title.downcase.delete_prefix("~").gsub(/[[:space:]]+/, "_").gsub(/__/, "_").gsub(/\A_|_\z/, "")
+    title.to_s.downcase.delete_prefix("~").gsub(/[[:space:]]+/, "_").gsub(/__/, "_").gsub(/\A_|_\z/, "")
   end
 
   def normalize_title
diff --git a/test/functional/wiki_pages_controller_test.rb b/test/functional/wiki_pages_controller_test.rb
index 5a4ad9c2b..0c8ae20b3 100644
--- a/test/functional/wiki_pages_controller_test.rb
+++ b/test/functional/wiki_pages_controller_test.rb
@@ -109,13 +109,6 @@ class WikiPagesControllerTest < ActionDispatch::IntegrationTest
         assert_response 404
       end
 
-      should "render for a negated tag" do
-        as(@user) { @wiki_page.update(title: "-aaa") }
-
-        get wiki_page_path(@wiki_page.id)
-        assert_redirected_to wiki_page_path(@wiki_page.title)
-      end
-
       should "work for a title containing dots" do
         as(@user) { create(:wiki_page, title: "...") }
 
diff --git a/test/unit/wiki_page_test.rb b/test/unit/wiki_page_test.rb
index 41b814a8a..32391cfb8 100644
--- a/test/unit/wiki_page_test.rb
+++ b/test/unit/wiki_page_test.rb
@@ -78,6 +78,29 @@ class WikiPageTest < ActiveSupport::TestCase
       end
     end
 
+    context "during title validation" do
+      # these values are allowed because they're normalized first
+      should allow_value(" foo ").for(:title).on(:create)
+      should allow_value("~foo").for(:title).on(:create)
+      should allow_value("_foo").for(:title).on(:create)
+      should allow_value("foo_").for(:title).on(:create)
+      should allow_value("foo__bar").for(:title).on(:create)
+      should allow_value("FOO").for(:title).on(:create)
+      should allow_value("foo bar").for(:title).on(:create)
+
+      should_not allow_value("").for(:title).on(:create)
+      should_not allow_value("___").for(:title).on(:create)
+      should_not allow_value("-foo").for(:title).on(:create)
+      should_not allow_value("/foo").for(:title).on(:create)
+      should_not allow_value("foo*bar").for(:title).on(:create)
+      should_not allow_value("foo,bar").for(:title).on(:create)
+      should_not allow_value("foo\abar").for(:title).on(:create)
+      should_not allow_value("café").for(:title).on(:create)
+      should_not allow_value("東方").for(:title).on(:create)
+      should_not allow_value("FAV:blah").for(:title).on(:create)
+      should_not allow_value("X"*171).for(:title).on(:create)
+    end
+
     context "with other names" do
       should "not allow artist wikis to have other names" do
         tag = create(:artist_tag)