diff --git a/app/logical/concerns/normalizable.rb b/app/logical/concerns/normalizable.rb
new file mode 100644
index 000000000..7cad97e61
--- /dev/null
+++ b/app/logical/concerns/normalizable.rb
@@ -0,0 +1,18 @@
+module Normalizable
+  extend ActiveSupport::Concern
+
+  class_methods do
+    def normalize(attribute, method_name)
+      define_method("#{attribute}=") do |value|
+        normalized_value = self.class.send(method_name, value)
+        super(normalized_value)
+      end
+    end
+
+    private
+
+    def normalize_text(text)
+      text.unicode_normalize(:nfc).normalize_whitespace.strip
+    end
+  end
+end
diff --git a/app/models/application_record.rb b/app/models/application_record.rb
index e162b39dd..fc8391890 100644
--- a/app/models/application_record.rb
+++ b/app/models/application_record.rb
@@ -3,6 +3,7 @@ class ApplicationRecord < ActiveRecord::Base
 
   include Deletable
   include Mentionable
+  include Normalizable
   extend HasBitFlags
   extend Searchable
 
diff --git a/app/models/wiki_page.rb b/app/models/wiki_page.rb
index 79922b98c..236ba0410 100644
--- a/app/models/wiki_page.rb
+++ b/app/models/wiki_page.rb
@@ -3,11 +3,13 @@ class WikiPage < ApplicationRecord
 
   META_WIKIS = ["list_of_", "tag_group:", "pool_group:", "howto:", "about:", "help:", "template:"]
 
-  before_validation :normalize_title
   before_validation :normalize_other_names
   before_save :update_dtext_links, if: :dtext_links_changed?
   after_save :create_version
 
+  normalize :title, :normalize_title
+  normalize :body, :normalize_text
+
   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
@@ -151,10 +153,6 @@ class WikiPage < ApplicationRecord
     title.to_s.downcase.delete_prefix("~").gsub(/[[:space:]]+/, "_").gsub(/__/, "_").gsub(/\A_|_\z/, "")
   end
 
-  def normalize_title
-    self.title = WikiPage.normalize_title(title)
-  end
-
   def normalize_other_names
     self.other_names = other_names.map { |name| WikiPage.normalize_other_name(name) }.uniq
   end
diff --git a/config/initializers/core_extensions.rb b/config/initializers/core_extensions.rb
index ef7dba48d..2456c6b9a 100644
--- a/config/initializers/core_extensions.rb
+++ b/config/initializers/core_extensions.rb
@@ -41,6 +41,19 @@ module Danbooru
         pattern = Regexp.escape(pattern).gsub(/\\\*/, ".*")
         match?(/\A#{pattern}\z/i)
       end
+
+      def normalize_whitespace
+        # Normalize various horizontal space characters to ASCII space.
+        text = gsub(/\p{Zs}|\t/, " ")
+
+        # Strip various zero width space characters.
+        text = text.gsub(/[\u180E\u200B\u200C\u200D\u2060\uFEFF]/, "")
+
+        # Normalize various line ending characters to CRLF.
+        text = text.gsub(/\r?\n|\r|\v|\f|\u0085|\u2028|\u2029/, "\r\n")
+
+        text
+      end
     end
   end
 end
diff --git a/test/unit/string_test.rb b/test/unit/string_test.rb
index 47224ba77..247c637e0 100644
--- a/test/unit/string_test.rb
+++ b/test/unit/string_test.rb
@@ -14,4 +14,32 @@ class StringTest < ActiveSupport::TestCase
       assert_equal('%*%', '*\**'.to_escaped_for_sql_like)
     end
   end
+
+  context "String#normalize_whitespace" do
+    should "normalize unicode spaces" do
+      assert_equal("foo bar", "foo bar".normalize_whitespace)
+      assert_equal("foo bar", "foo\u00A0bar".normalize_whitespace)
+      assert_equal("foo bar", "foo\u3000bar".normalize_whitespace)
+    end
+
+    should "strip zero width characters" do
+      assert_equal("foobar", "foo\u180Ebar".normalize_whitespace)
+      assert_equal("foobar", "foo\u200Bbar".normalize_whitespace)
+      assert_equal("foobar", "foo\u200Cbar".normalize_whitespace)
+      assert_equal("foobar", "foo\u200Dbar".normalize_whitespace)
+      assert_equal("foobar", "foo\u2060bar".normalize_whitespace)
+      assert_equal("foobar", "foo\uFEFFbar".normalize_whitespace)
+    end
+
+    should "normalize line endings" do
+      assert_equal("foo\r\nbar", "foo\r\nbar".normalize_whitespace)
+      assert_equal("foo\r\nbar", "foo\nbar".normalize_whitespace)
+      assert_equal("foo\r\nbar", "foo\rbar".normalize_whitespace)
+      assert_equal("foo\r\nbar", "foo\vbar".normalize_whitespace)
+      assert_equal("foo\r\nbar", "foo\fbar".normalize_whitespace)
+      assert_equal("foo\r\nbar", "foo\u0085bar".normalize_whitespace)
+      assert_equal("foo\r\nbar", "foo\u2028bar".normalize_whitespace)
+      assert_equal("foo\r\nbar", "foo\u2029bar".normalize_whitespace)
+    end
+  end
 end
diff --git a/test/unit/wiki_page_test.rb b/test/unit/wiki_page_test.rb
index 32391cfb8..150561e3b 100644
--- a/test/unit/wiki_page_test.rb
+++ b/test/unit/wiki_page_test.rb
@@ -78,6 +78,19 @@ class WikiPageTest < ActiveSupport::TestCase
       end
     end
 
+    context "the wiki body" do
+      should "be normalized to NFC" do
+        # \u00E9: é; \u0301: acute accent
+        @wiki = create(:wiki_page, body: "Poke\u0301mon")
+        assert_equal("Pok\u00E9mon", @wiki.body)
+      end
+
+      should "normalize line endings and trim spaces" do
+        @wiki = create(:wiki_page, body: " foo\nbar\n")
+        assert_equal("foo\r\nbar", @wiki.body)
+      end
+    end
+
     context "during title validation" do
       # these values are allowed because they're normalized first
       should allow_value(" foo ").for(:title).on(:create)