Change Full Size image width to match theme

The column width in WordPress’s default theme Kubrick is 500px. Therefore, the default (maximum) image size is 500px. The column width of the blog I am posting to is 614px. You can set a global variable to change this setting. Create if not already existing functions.php in your theme directory. Define your maximum media width (that is “Full Size” in the Gallery interface):

<?php
$content_width = 614;
?>

I’ve set mine to 614 pixels since that is the width of my div with the class “.entry” minus padding. If this does not work, some have solved this problem with $GLOBALS['content_width'] = 614; also. You can view this setting at a post at RachelSteely.com.

Default media to Full Size

I prefer to justify my media (align left and right) to the column width. To do this, set default selected size to “Full Size” by changing the code in /wp-admin/includes/media.php. Move the ‘checked’ radio attribute from Medium to Full Size.

Line 458:

" : '' ) . "<input type='radio' name='attachments[$post->ID][image-size]' id='image-size-medium-$post->ID' value='medium' checked='checked' />
<label for='image-size-medium-$post->ID'>" . __('Medium') . "</label>
<input type='radio' name='attachments[$post->ID][image-size]' id='image-size-full-$post->ID' value='full' />


change to

" : '' ) . "<input type='radio' name='attachments[$post->ID][image-size]' id='image-size-medium-$post->ID' value='medium' />
<label for='image-size-medium-$post->ID'>" . __('Medium') . "</label>
<input type='radio' name='attachments[$post->ID][image-size]' id='image-size-full-$post->ID' value='full' checked='checked' />

And that’s it! Happy uploading with the new and improved (and customized) WordPress media gallery.