Is this more what you are looking for? I made a single frame for all the buttons, then when buttons are created within that frame, pack them as anchored to the west. The default packing will cause them to be put one on top of another (vertically). Update: don't need -side, just -anchor=>'w' for each button's pack 
use Tk;
use strict;
use warnings;

# Main Window
my $mw = new MainWindow;

#GUI Building Area
my @style_sizes_array = qw(XXS XS S M L XL XXL XXXL);

my $buttonFrame = $mw->Frame()->pack();

    #checkbutton sizes setup
    for (my $ctr = 0; $ctr < @style_sizes_array; $ctr++){
        my $size_type = $style_sizes_array[$ctr];

        $buttonFrame ->Checkbutton(-text => $size_type, -padx=>20, 
                          -variable => \$ctr)->pack(-anchor=>'w');
    }

MainLoop();

[download]

In reply to Re: checkbutton alignment by Marshall
in thread checkbutton alignment by skywalker

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.