diff --git a/Data/Scripts.rvdata2 b/Data/Scripts.rvdata2
index d0b247c..a1451c1 100644
Binary files a/Data/Scripts.rvdata2 and b/Data/Scripts.rvdata2 differ
diff --git a/Scripts/Window_Resizer.rb b/Scripts/Window_Resizer.rb
new file mode 100644
index 0000000..a8001d1
--- /dev/null
+++ b/Scripts/Window_Resizer.rb
@@ -0,0 +1,55 @@
+#==============================================================================
+# ■ Window Resize Toggle (F5) - Auto-Center + Taskbar Offset
+#------------------------------------------------------------------------------
+# Cycles through safe window sizes and auto-centers the window to ensure it
+# stays fully visible within the monitor bounds. Nudges window upward to avoid
+# overlapping the taskbar at the bottom.
+#==============================================================================
+
+module WindowScaler
+  # Define fixed window sizes [width, height]
+  SIZES = [
+    [544, 416],     # 1.0x native
+    [816, 624],     # 1.5x
+    [1088, 832],    # 2.0x
+    [1360, 1040],   # 2.5x
+    [1632, 1248],   # 3.0x
+    [1856, 1392],   # ~3.4x
+  ]
+
+  TASKBAR_OFFSET = 20  # Move window upward to avoid taskbar
+end
+
+class << Graphics
+  alias resize_update update
+  def update
+    resize_update
+    WindowResize.update
+  end
+end
+
+module WindowResize
+  @index = 0
+
+  def self.update
+    if Input.trigger?(:F5)
+      @index = (@index + 1) % WindowScaler::SIZES.size
+      apply_size(*WindowScaler::SIZES[@index])
+    end
+  end
+
+  def self.apply_size(width, height)
+    # Get screen resolution
+    screen_width  = Win32API.new('user32', 'GetSystemMetrics', ['I'], 'I').call(0)
+    screen_height = Win32API.new('user32', 'GetSystemMetrics', ['I'], 'I').call(1)
+
+    # Calculate centered position, nudged up by TASKBAR_OFFSET
+    x = [(screen_width - width) / 2, 0].max
+    y = [(screen_height - height) / 2 - WindowScaler::TASKBAR_OFFSET, 0].max
+
+    # Resize and move window
+    hwnd = Win32API.new('user32', 'FindWindowA', ['P', 'P'], 'L').call("RGSS Player", nil)
+    move_window = Win32API.new('user32', 'MoveWindow', %w(L L L L L L), 'L')
+    move_window.call(hwnd, x, y, width, height, 1)
+  end
+end
diff --git a/YAML/Scripts.yaml b/YAML/Scripts.yaml
index cc0f6a1..32c69cf 100644
--- a/YAML/Scripts.yaml
+++ b/YAML/Scripts.yaml
@@ -452,11 +452,14 @@
   - 'メッセージスキップ機能'
   - '_.24.rb'
 - - !!int '152'
+  - 'Window Resizer'
+  - 'Window_Resizer.rb'
+- - !!int '153'
   - '▼ メイン'
   - !!null 'null'
-- - !!int '153'
+- - !!int '154'
   - 'Main'
   - 'Main.rb'
-- - !!int '154'
+- - !!int '155'
   - ''
   - !!null 'null'