diff --git a/dbapp/mainapp/views/points_averaging.py b/dbapp/mainapp/views/points_averaging.py
index e9266f9..bfea7a3 100644
--- a/dbapp/mainapp/views/points_averaging.py
+++ b/dbapp/mainapp/views/points_averaging.py
@@ -149,12 +149,21 @@ class PointsAveragingAPIView(LoginRequiredMixin, View):
         """
         Get interval key for a timestamp.
         
-        Day: 08:00 - 19:00 -> "YYYY-MM-DD_day"
-        Night: 19:00 - 08:00 -> "YYYY-MM-DD_night" (date of the start of night)
+        Weekend: Friday 19:00 - Monday 08:00 -> "YYYY-MM-DD_weekend" (date of Friday)
+        Day (weekdays): 08:00 - 19:00 -> "YYYY-MM-DD_day"
+        Night (weekdays): 19:00 - 08:00 -> "YYYY-MM-DD_night" (date of the start of night)
         """
         hour = timestamp.hour
         date = timestamp.date()
+        weekday = date.weekday()  # 0=Monday, 4=Friday, 5=Saturday, 6=Sunday
         
+        # Check if timestamp falls into weekend interval (Fri 19:00 - Mon 08:00)
+        if self._is_weekend_interval(date, hour, weekday):
+            # Find the Friday date for this weekend
+            friday_date = self._get_friday_for_weekend(date, hour, weekday)
+            return f"{friday_date.strftime('%Y-%m-%d')}_weekend"
+        
+        # Weekday intervals
         if 8 <= hour < 19:
             # Day interval
             return f"{date.strftime('%Y-%m-%d')}_day"
@@ -166,6 +175,39 @@ class PointsAveragingAPIView(LoginRequiredMixin, View):
             prev_date = date - timedelta(days=1)
             return f"{prev_date.strftime('%Y-%m-%d')}_night"
     
+    def _is_weekend_interval(self, date, hour, weekday):
+        """
+        Check if the given timestamp falls into weekend interval.
+        Weekend: Friday 19:00 - Monday 08:00
+        """
+        # Friday after 19:00
+        if weekday == 4 and hour >= 19:
+            return True
+        # Saturday (all day)
+        if weekday == 5:
+            return True
+        # Sunday (all day)
+        if weekday == 6:
+            return True
+        # Monday before 08:00
+        if weekday == 0 and hour < 8:
+            return True
+        return False
+    
+    def _get_friday_for_weekend(self, date, hour, weekday):
+        """
+        Get the Friday date for the weekend interval that contains this timestamp.
+        """
+        if weekday == 4:  # Friday
+            return date
+        elif weekday == 5:  # Saturday
+            return date - timedelta(days=1)
+        elif weekday == 6:  # Sunday
+            return date - timedelta(days=2)
+        elif weekday == 0 and hour < 8:  # Monday before 08:00
+            return date - timedelta(days=3)
+        return date
+    
     def _process_group(self, group_key, points):
         """
         Process a group of points: calculate average and check for outliers.
@@ -184,6 +226,10 @@ class PointsAveragingAPIView(LoginRequiredMixin, View):
         
         if interval_type == 'day':
             interval_label = f"{interval_date.strftime('%d.%m.%Y')} День (08:00-19:00)"
+        elif interval_type == 'weekend':
+            # Weekend starts Friday 19:00, ends Monday 08:00
+            monday_date = interval_date + timedelta(days=3)
+            interval_label = f"{interval_date.strftime('%d.%m.%Y')} Выходные (Пт 19:00 - Пн 08:00, {monday_date.strftime('%d.%m.%Y')})"
         else:
             interval_label = f"{interval_date.strftime('%d.%m.%Y')} Ночь (19:00-08:00)"