diff --git a/events/services/calendar.py b/events/services/calendar.py
index 8037b0d..e7019f8 100644
--- a/events/services/calendar.py
+++ b/events/services/calendar.py
@@ -19,10 +19,13 @@ import datetime
 
 from django.utils import timezone
 
-#: The week grid's default visible hours -- expanded automatically (see week_grid)
-#: if an event falls outside it, so nothing is ever clipped out of view.
-DEFAULT_DAY_START_HOUR = 8
-DEFAULT_DAY_END_HOUR = 22
+#: The week grid's visible hours -- the full day, always, so nothing is ever
+#: scrolled out of view regardless of what time events happen to fall at (this
+#: used to default to a narrower 08:00-22:00 window, only widening for events
+#: outside it -- a very early or very late one still left the grid clipped at
+#: the other end, e.g. midnight..22:00 rather than the full day).
+DEFAULT_DAY_START_HOUR = 0
+DEFAULT_DAY_END_HOUR = 24
 
 #: Floor on a block's rendered height, in percent of the visible hour span -- a very
 #: short event (a 15-minute weigh-in) would otherwise render as a sliver too thin to
diff --git a/events/tests.py b/events/tests.py
index 6194332..19a7f7b 100644
--- a/events/tests.py
+++ b/events/tests.py
@@ -1388,27 +1388,28 @@ class CalendarGridTests(EventsTestBase):
     def test_add_months_rolls_over_the_year(self):
         self.assertEqual(add_months(date(2026, 11, 15), 2), date(2027, 1, 1))
 
-    def test_week_grid_places_an_event_within_the_default_hours(self):
+    def test_week_grid_always_covers_the_full_day(self):
         monday = date(2026, 8, 17)
         event = self.make_event(start=self.at(monday, 10), end=self.at(monday, 11, 30))
 
         grid = week_grid([event], monday)
 
-        self.assertEqual(grid["day_start_hour"], 8)
-        self.assertEqual(grid["day_end_hour"], 22)
-        span = 22 - 8
+        self.assertEqual(grid["day_start_hour"], 0)
+        self.assertEqual(grid["day_end_hour"], 24)
+        self.assertEqual(grid["hours"], list(range(0, 25)))
+        span = 24
         block = grid["days"][0]["blocks"][0]
-        self.assertAlmostEqual(block["top_pct"], 100 * (10 - 8) / span, places=2)
+        self.assertAlmostEqual(block["top_pct"], 100 * 10 / span, places=2)
         self.assertAlmostEqual(block["height_pct"], 100 * 1.5 / span, places=2)
 
-    def test_week_grid_expands_the_hours_for_an_early_or_late_event(self):
+    def test_week_grid_still_covers_an_event_starting_at_midnight_or_ending_near_it(self):
         monday = date(2026, 8, 17)
-        event = self.make_event(start=self.at(monday, 6), end=self.at(monday, 23))
+        event = self.make_event(start=self.at(monday, 0), end=self.at(monday, 23, 45))
 
         grid = week_grid([event], monday)
 
-        self.assertEqual(grid["day_start_hour"], 6)
-        self.assertEqual(grid["day_end_hour"], 23)
+        self.assertEqual(grid["day_start_hour"], 0)
+        self.assertEqual(grid["day_end_hour"], 24)
 
     def test_week_grid_excludes_events_outside_the_week(self):
         monday = date(2026, 8, 17)