That chart is way too small for IPAsI use Brewer's friend to work up recipes. Punch in your grains and hops, and it spits out what you need. There is also a graph available on line that will tell you what is a balanced, mild or bitter beer for a given original gravity. It's a useful tool because low OG beers tend to seem more bitter with the same IBUs as high OG beers. Here is a link: http://finnhillbrewing.blogspot.com/2011/04/bugu-ratios.html