We’re using a custom theme on this project, so this may be theme-specific, but if you’re using Magento and Google Checkout and the Google Checkout button is incredibly tiny (13px tall specifically), then you have a style in your CSS file that is setting all input types, including the Google Checkout button, to be 13px tall.

To fix this, edit design/frontend/[THEME NAME]/default/template/googlecheckout/link.phtml

Find the line, around line 34, that looks like:

<input type=”image”  src=”<?php echo $this->htmlEscape($this->getImageUrl())?>”

And edit it, adding the section in bold:

<input type=”image” style=”height:46px;” src=”<?php echo $this->htmlEscape($this->getImageUrl())?>”

You’ll want to change 46px to an appropriate value for the size of Google Checkout button you are using; 46px is for the large version of the button.