diff --git a/django/utils/feedgenerator.py b/django/utils/feedgenerator.py
index e23fde71aef19..28a83f2f42654 100644
--- a/django/utils/feedgenerator.py
+++ b/django/utils/feedgenerator.py
@@ -285,7 +285,7 @@ def add_item_elements(self, handler, item):
 
 class Atom1Feed(SyndicationFeed):
     # Spec: http://atompub.org/2005/07/11/draft-ietf-atompub-format-10.html
-    mime_type = 'application/atom+xml; charset=utf8'
+    mime_type = 'application/atom+xml; charset=utf-8'
     ns = u"http://www.w3.org/2005/Atom"
 
     def write(self, outfile, encoding):
diff --git a/tests/regressiontests/signing/tests.py b/tests/regressiontests/signing/tests.py
index 0b0cacf10ef7c..a9065131da10c 100644
--- a/tests/regressiontests/signing/tests.py
+++ b/tests/regressiontests/signing/tests.py
@@ -13,7 +13,7 @@ def test_signature(self):
         for s in (
             'hello',
             '3098247:529:087:',
-            u'\u2019'.encode('utf8'),
+            u'\u2019'.encode('utf-8'),
         ):
             self.assertEqual(
                 signer.signature(s),
diff --git a/tests/regressiontests/utils/feedgenerator.py b/tests/regressiontests/utils/feedgenerator.py
index 26c60ea420abe..bcb4286e8995d 100644
--- a/tests/regressiontests/utils/feedgenerator.py
+++ b/tests/regressiontests/utils/feedgenerator.py
@@ -66,6 +66,6 @@ def test_atom1_mime_type(self):
         """
         atom_feed = feedgenerator.Atom1Feed("title", "link", "description")
         self.assertEqual(
-            atom_feed.mime_type, "application/atom+xml; charset=utf8"
+            atom_feed.mime_type, "application/atom+xml; charset=utf-8"
         )