diff --git a/Lib/idlelib/help_about.py b/Lib/idlelib/help_about.py
index a2ac3166c34..967f0342a10 100644
--- a/Lib/idlelib/help_about.py
+++ b/Lib/idlelib/help_about.py
@@ -2,7 +2,8 @@
 
 """
 import os
-from platform import python_version
+import sys
+from platform import python_version, architecture
 
 from tkinter import Toplevel, Frame, Label, Button, PhotoImage
 from tkinter import SUNKEN, TOP, BOTTOM, LEFT, X, BOTH, W, EW, NSEW, E
@@ -10,6 +11,14 @@ from tkinter import SUNKEN, TOP, BOTTOM, LEFT, X, BOTH, W, EW, NSEW, E
 from idlelib import textview
 
 
+def build_bits():
+    "Return bits for platform."
+    if sys.platform == 'darwin':
+        return '64' if sys.maxsize > 2**32 else '32'
+    else:
+        return architecture()[0][:2]
+
+
 class AboutDialog(Toplevel):
     """Modal about dialog for idle
 
@@ -28,11 +37,12 @@ class AboutDialog(Toplevel):
         self.geometry("+%d+%d" % (
                         parent.winfo_rootx()+30,
                         parent.winfo_rooty()+(30 if not _htest else 100)))
-        self.bg = "#707070"
-        self.fg = "#ffffff"
+        self.bg = "#bbbbbb"
+        self.fg = "#000000"
         self.create_widgets()
         self.resizable(height=False, width=False)
-        self.title(title or f'About IDLE {python_version()}')
+        self.title(title or
+                   f'About IDLE {python_version()} ({build_bits()} bit)')
         self.transient(parent)
         self.grab_set()
         self.protocol("WM_DELETE_WINDOW", self.ok)
diff --git a/Lib/idlelib/idle_test/test_help_about.py b/Lib/idlelib/idle_test/test_help_about.py
index be1fadd58f4..08c38a515da 100644
--- a/Lib/idlelib/idle_test/test_help_about.py
+++ b/Lib/idlelib/idle_test/test_help_about.py
@@ -5,12 +5,15 @@ Coverage: 100%
 from test.support import requires, findfile
 from tkinter import Tk, TclError
 import unittest
+from unittest import mock
 from idlelib.idle_test.mock_idle import Func
 from idlelib.idle_test.mock_tk import Mbox_func
 from idlelib.help_about import AboutDialog as About
+from idlelib import help_about
 from idlelib import textview
 import os.path
-from platform import python_version
+from platform import python_version, architecture
+
 
 class LiveDialogTest(unittest.TestCase):
     """Simulate user clicking buttons other than [Close].
@@ -31,6 +34,9 @@ class LiveDialogTest(unittest.TestCase):
         cls.root.destroy()
         del cls.root
 
+    def test_build_bits(self):
+        self.assertIn(help_about.build_bits(), ('32', '64'))
+
     def test_dialog_title(self):
         """Test about dialog title"""
         self.assertEqual(self.dialog.title(), 'About IDLE')
@@ -99,7 +105,9 @@ class DefaultTitleTest(unittest.TestCase):
 
     def test_dialog_title(self):
         """Test about dialog title"""
-        self.assertEqual(self.dialog.title(), f'About IDLE {python_version()}')
+        self.assertEqual(self.dialog.title(),
+                         f'About IDLE {python_version()}'
+                         f' ({help_about.build_bits()} bit)')
 
 
 class CloseTest(unittest.TestCase):