Pre boil gravity 1.050 13 brix Post boil gravity 1.058 15 brix Final gravity 1.012 6.0% ABV
Based on boiling 12.00 gallonsliters at 1.050 for 60 minutes, this will decrease your wort by 1.00 gallonsliters, bringing your after boil OG to 1.054. You wanted an OG of 1.057. It looks like it will be under.