There are many guides and review sites to determine the best choices for your dog's diet. Some claim to be independent but are sponsored by large pet food companies. Here are three that are the most impartial with opinions we agree with the most, having done much of the same research. They are in no particular order. Please note that we personally only feed home made and wet food.
The Dog Food Adviser provides a truly comprehensive breakdown of brands and ingredients. It's extremely detailed advice from Mike Sagman and pet food experts than even most Vets don't know. A true must-read for anyone interested in the pet food industry or who's buying an expensive "prescription food".
Susan Thixton puts out expert recommendations every year. Since she is 100% consumer supported and does not permit advertising to influence the site, the list costs $10 - and is well worth it. And there is a lot of other important information on this site that is free. Check out The Truth About Pet Food
Why the class action lawsuit directed at Purina in 2015 had little to no effect on pet food industry marketing practices plus comprehensive analysis at Reviews.com