As a Professional Bicycle Mechanic I am deeply offended at the thought of using WD-40 on a bicycle chain. If you care anything at all about your bicycle you will use bicycle-specific formulations. You can tell the good ones by their price tag: spend at least $30/ounce and you can be comforted by the knowledge that you are doing everything possible to preserve your noble steed.
Really good stuff, of course, is significantly more expensive and should come in a bottle with appropriate graphics and technical specifications that you don't necessarily need to understand but that you should at least memorize for discussion at the coffee stop.
All this applies, BTW, only for users of 11 speed chain. Users of ten (and fewer) speed chain can use whatever they want on their junky old clunkers. I don't really have time to discuss things with those losers.