diff --git a/ui_scaling_test.py b/ui_scaling_test.py
new file mode 100644
index 0000000..293636a
--- /dev/null
+++ b/ui_scaling_test.py
@@ -0,0 +1,53 @@
+import tkinter as tk
+from tkinter import ttk
+
+import setup_tool_dynamic
+
+
+class ScalingTestTool(setup_tool_dynamic.ModernWowSetupTool):
+    """Temporary UI-only build for validating Windows DPI/display scaling."""
+
+    def __init__(self, root):
+        super().__init__(root)
+
+        # UI-only test: preserve every installer behavior and only change how
+        # the existing Tk window allocates and exposes its controls.
+        root.title("WoW Vanilla 1.12 Modernization Tool [UI Scaling Test]")
+        root.resizable(True, True)
+
+        # Reserve the bottom action button before the expandable notebook.
+        # This keeps Apply accessible when Windows text/DPI scaling makes the
+        # notebook request more vertical space than the original 680x660 size.
+        notebook = next(
+            (child for child in root.winfo_children() if isinstance(child, ttk.Notebook)),
+            None,
+        )
+        apply_button = getattr(self, "apply_button", None)
+        if notebook is not None and apply_button is not None:
+            notebook.pack_forget()
+            apply_button.pack_forget()
+            apply_button.pack(side="bottom", pady=10, fill="x", padx=20)
+            notebook.pack(fill="both", expand=True, padx=10, pady=(5, 10))
+
+        root.update_idletasks()
+
+        # Prefer the widgets' requested size when the monitor has room, while
+        # keeping a margin so the window remains reachable on smaller displays.
+        screen_width = max(1, root.winfo_screenwidth())
+        screen_height = max(1, root.winfo_screenheight())
+        max_width = max(640, screen_width - 80)
+        max_height = max(520, screen_height - 80)
+
+        requested_width = max(680, root.winfo_reqwidth())
+        requested_height = max(660, root.winfo_reqheight())
+        width = min(requested_width, max_width)
+        height = min(requested_height, max_height)
+
+        root.geometry(f"{width}x{height}")
+        root.minsize(min(640, max_width), min(520, max_height))
+
+
+if __name__ == "__main__":
+    root = tk.Tk()
+    app = ScalingTestTool(root)
+    root.mainloop()