If your site is forcing the iPad to view a mobile site view, you can long press on the reload icon in the URL bar and request the desktop version of the site.
Some third party apps (like iCab Mobile) can change their browser ID; so you can view the site as Safari Mobile, Safari Desktoip, Explorer, Firefox, etc. Note that this only changes what the site thinks the browser is. It does not change the browser engine; which is still iOS’s Safari engine in almost all apps. Exceptions like Puffin get around this by running the browser on a remote server.
Disclaimer: I’m not a webdev.