Up to the 2012 model year
The newer Audi's do not come with a dipstick from the factory. Instead, they have an oil sensor that displays the oil level in the cars MMI display. If your like most car guys out there, you would still like a fool proof way to check your oil and do preventative maintenance. The engine still has the provision for a dipstick, but instead of the actual stick, it is plugged off.
This Genuine dipstick from Audi will do the trick. All you have to do is remove the plug and set it off to the side. Then, insert the new dipstick into where the plug was and you can now check your oil the proper way.