That is really a hard question to ask, with all the strong strains out there these days. The strongest I have ever heard of was in an article about Magnus Genetics Warlock. From what the article said Illinois st trooper busted some guy with some Warlock that registered at 29%. I think that must have been some strange pheno though because The the plants they grew in Holland were an average 22% to 23%. I have grown the shit twice going to be three times and all I can say is DANK!!!!!!!!!!