I use the online version of the Catechism of the Catholic Church at the Vatican web site all the time, so I decided to make an upgraded version of their index page (here). The improvements on this version include:

The links now open pages in new tabs. I’ve added links to the Latin version, to make it easier to check the original. I’ve added the passage numbers in parentheses after each link, to make it easier to look up passages by their number.

Feel free to bookmark this page. A short link for it is JimmyAkin.com/catechism