diff --git a/api/scpca_portal/test/test_utils.py b/api/scpca_portal/test/test_utils.py
index a4cb17d2..00367228 100644
--- a/api/scpca_portal/test/test_utils.py
+++ b/api/scpca_portal/test/test_utils.py
@@ -1,3 +1,6 @@
+from datetime import date
+from unittest.mock import patch
+
 from django.test import TestCase
 
 from scpca_portal import utils
@@ -37,3 +40,10 @@ def test_join_multiple_items(self):
     def test_join_single_item(self):
         items = ("single item",)
         self.assertEqual(utils.join_workflow_versions(items), items[0])
+
+
+class TestGetToday(TestCase):
+    @patch("scpca_portal.utils.datetime")
+    def test_format(self, mock_date):
+        mock_date.today.return_value = date(2022, 10, 8)
+        self.assertEqual(utils.get_today_string(), "2022-10-08")
diff --git a/api/scpca_portal/utils.py b/api/scpca_portal/utils.py
index ded5868c..be3b46ca 100644
--- a/api/scpca_portal/utils.py
+++ b/api/scpca_portal/utils.py
@@ -25,6 +25,6 @@ def join_workflow_versions(workflow_versions):
     return ", ".join(sorted(set(workflow_versions)))
 
 
-def get_today_string(format: str = "%Y-%M-%d"):
+def get_today_string(format: str = "%Y-%m-%d"):
     """Returns today's date formatted. Defaults to ISO 8601."""
     return datetime.today().strftime(format)