I was trying to formulate a recipe earlier and thought I had it all figured out. When I mixed it this evening, it came out to a MUCH higher gravity than expected. There's an error somewhere with the conversion where the calculator thinks 1 US gallon = 2 US quarts, not the 4 that it should be. Anyone else able to replicate this error?

edit: Actually, playing around a bit more, it seems that all the other US units are messed up with respect to gallons.