diff --git a/Lib/idlelib/aboutDialog.py b/Lib/idlelib/aboutDialog.py
index 43a13135aee..07345180f91 100644
--- a/Lib/idlelib/aboutDialog.py
+++ b/Lib/idlelib/aboutDialog.py
@@ -66,12 +66,7 @@ class AboutDialog(Toplevel):
         labelPythonVer = Label(frameBg, text='Python version:  ' + \
                                sys.version.split()[0], fg=self.fg, bg=self.bg)
         labelPythonVer.grid(row=9, column=0, sticky=W, padx=10, pady=0)
-        # handle weird tk version num in windoze python >= 1.6 (?!?)
-        tkVer = repr(TkVersion).split('.')
-        tkVer[len(tkVer)-1] = str('%.3g' % (float('.'+tkVer[len(tkVer)-1])))[2:]
-        if tkVer[len(tkVer)-1] == '':
-            tkVer[len(tkVer)-1] = '0'
-        tkVer = '.'.join(tkVer)
+        tkVer = self.tk.call('info', 'patchlevel')
         labelTkVer = Label(frameBg, text='Tk version:  '+
                            tkVer, fg=self.fg, bg=self.bg)
         labelTkVer.grid(row=9, column=1, sticky=W, padx=2, pady=0)
diff --git a/Misc/NEWS b/Misc/NEWS
index deb0d4e2bae..161776daa04 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -29,6 +29,9 @@ Library
 IDLE
 ----
 
+- Issue #17657: Show full Tk version in IDLE's about dialog.
+  Patch by Todd Rovito.
+
 - Issue #17613: Prevent traceback when removing syntax colorizer in IDLE.
 
 - Issue #1207589: Backwards-compatibility patch for right-click menu in IDLE.