Diablo 3 Exp Timer is very simple and yet very powerfull Paragon Level Calculator. Choose your level, type your experience points and click "Record!". Go play and make some hardcore exping ;) After some time go back to this website and update your exp by retyping your current exp value and hit "Record!" button again. You will see your personal Diablo 3 Paragon Level Chart with all usefull informations like time left to level up, exp per hour ratio, exp for next level and much more!
Select your Diablo 3 Paragon Level. If you are level 60 without Paragon choose 00.
Check in-game your experience points and type them on website.
Press "Record!" button.
Keep play Diablo 3 and sometimes ALT-TAB to website to put your new exp points. After 2nd update you will get table like this one below with usefull informations about your progress in Paragon Level. Enjoy!
To make typing exp faster you can leave 000 at the end. For example instead 150,746,132 you can type 150,746,000. It won't make big difference in calculation but it takes much less to type because 000 is already there.
When you level up, you don't need change your paragon level, which is immposible anyway. Just type your new exp points and calculator will notice you leveled up from smaller exp amount.